Apparatus and method for transmitting or receiving broadcast signal

ABSTRACT

A method for transmitting a broadcast signal is disclosed. The method for transmitting a broadcast signal according to an embodiment of the present invention includes performing delivery layer processing of a broadcast service data and signaling information with respect to the broadcast service data, performing UDP/IP encapsulation of a broadcast service data and signaling information with respect to the broadcast service data and performing physical layer processing of a broadcast service data and signaling information with respect to the broadcast service data.

TECHNICAL FIELD

The present invention relates to an apparatus for transmitting abroadcast signal, an apparatus for receiving a broadcast signal, amethod for transmitting a broadcast signal and a method for receiving abroadcast signal.

BACKGROUND ART

As analog broadcast signal transmission comes to an end, varioustechnologies for transmitting/receiving digital broadcast signals havebeen developed. A digital broadcast signal may include a larger amountof video/audio data than an analog broadcast signal and may furtherinclude various types of additional data in addition to the video/audiodata.

DISCLOSURE Technical Problem

A digital broadcast system may provide HD (high definition) images,multi-channel audio and various additional services. However, datatransmission efficiency for transmission of large amounts of data,robustness of transmission/reception networks and network flexibility inconsideration of mobile reception equipment need to be improved fordigital broadcast.

Technical Solution

The present invention proposes a method for transmitting a broadcastsignal and an apparatus for transmitting a broadcast signal.

A method for transmitting a broadcast signal according to an embodimentof the present invention may include encoding a broadcast service databased on a delivery protocol; generating SLS information and SLTinformation with respect to the broadcast service data, wherein the SLSinformation provides a discovery and an acquisition of the broadcastservice data, and wherein the SLT information provides a discovery and abasic service list building of the SLS information; encoding the SLSinformation based on the delivery protocol; performing respective UDP(User Datagram Protocol)/IP (Internet Protocol) encapsulations of Lowlevel Signaling (LLS) information including the broadcast service data,the SLS information and the SLT information; and generating a signalframe by performing physical layer processing of the broadcast servicedata, the SLS information and the SLT information, and the deliveryprotocol may include at least one of Real-Time Object Delivery overUnidirectional Transport (ROUTE) protocol or MPEG Media Transport (MMT)protocol.

In addition, in an embodiment of the present invention, the LLSinformation may be carried as a payload of an IP packet that has apredetermined address and port number. In addition, the LLS informationmay include Emergency Alert (EA) related signaling information.

In addition, in an embodiment of the present invention, the EA relatedsignaling information may correspond to a Common Alerting Protocol (CAP)message.

In addition, in an embodiment of the present invention, the EA relatedsignaling information may include signaling information for a rich mediacontent transmission, and when the rich media content is deliveredthrough broadband, the EA related signaling information may indicateUniform Resource Locator (URL) information for receiving the rich mediacontent, and when the rich media content is delivered through broadcast,the EA related signaling information may indicate LCT channelinformation in which the rich media content is delivered.

In addition, in an embodiment of the present invention, the SLTinformation may include service category information, and a servicecategory indicated by the service category information may include alinear A/V service, a linear audio only service, an application-basedservice and an EA service, and when the rich media content for EA isdelivered to the EA service, the EA related signaling information mayinclude service ID information that delivers the rich media content.

In addition, in an embodiment of the present invention, when the signalframe includes the EA related signaling information, physical layersignaling information of the signal frame may indicate wake-up from astandby mode of a receiver, and includes wake-up signal indicating awake-up version.

A broadcast signal transmitter according to an embodiment of the presentinvention that performs the method for transmitting a broadcast signalmay include a signaling generator configured to generate Service LayerSignaling (SLS) information and a basic service list building providinga discovery and an acquisition of a broadcast service data and ServiceList Table (SLT) information providing an acquisition of the SLSinformation; a delivery layer encoder configured to encode the broadcastservice data and the SLS information based on at least one deliveryprotocol of Real-Time Object Delivery over Unidirectional Transport(ROUTE) protocol or MPEG Media Transport (MMT) protocol; a UDP/IPencapsulator configured to perform respective UDP (User DatagramProtocol)/IP (Internet Protocol) encapsulations of Low level Signaling(LLS) information including the broadcast service data, the SLSinformation and the SLT information; and a physical layer processorconfigured to generate a signal frame by performing physical layerprocessing of the broadcast service data, the SLS information and theSLT information.

Technical Effects

The present invention may process data according to servicecharacteristics to control Quality of Services (QoS) for each service orservice component, thereby providing various broadcast services.

The present invention may achieve transmission flexibility bytransmitting various broadcast services through the same radio frequency(RF) signal bandwidth.

The present invention may provide a method and apparatus fortransmitting/receiving a broadcast signal capable of receiving digitalbroadcast signals without an error even in the case of using a mobilereception device or in an indoor environment.

The present invention may support a next generation broadcast serviceefficiently in the environment that supports the hybrid broadcast thatuses a terrestrial broadcast network and an Internet network.

Hereinafter, the additional effects of the present invention may bedescribed together with the construction of the invention.

DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a protocol stack according to an embodimentof the present invention.

FIG. 2 is a diagram showing a service discovery procedure according toone embodiment of the present invention.

FIG. 3 is a diagram showing a low level signaling (LLS) table and aservice list table (SLT) according to one embodiment of the presentinvention.

FIG. 4 is a diagram showing a USBD and an S-TSID delivered through ROUTEaccording to one embodiment of the present invention.

FIG. 5 is a diagram showing a USBD delivered through MMT according toone embodiment of the present invention.

FIG. 6 is a diagram showing link layer operation according to oneembodiment of the present invention.

FIG. 7 is a diagram showing a link mapping table (LMT) according to oneembodiment of the present invention.

FIG. 8 illustrates a configuration of a broadcast signal transmissionapparatus for future broadcast services according to an embodiment ofthe present invention.

FIG. 9 illustrates a write operation of a time interleaver according toan embodiment of the present invention.

FIG. 10 illustrates an interlaving address generator including a mainpseudo-random binary sequence (PRBS) generator and a sub-PRBS generatoraccording to each FFT mode which are included in a frequencyinterleavaer according to an embodiment of the present invention.

FIG. 11 illustrates a service delivery and signaling structure accordingto an embodiment of the present invention.

FIG. 12 illustrates logical entity and relationship of a servicemanagement, delivery and physical layers according to an embodiment ofthe present invention.

FIG. 13 illustrates a method for using a service signaling forbootstrapping and service discovery according to an embodiment of thepresent invention.

FIG. 14 illustrates SLT information according to an embodiment of thepresent invention.

FIG. 15 illustrates an XML format of the SLT according to an embodimentof the present invention.

FIG. 16 illustrates an XML format of InetSigLocation informationaccording to an embodiment of the present invention.

FIG. 17 illustrates a service layer signaling data model according to anembodiment of the present invention.

FIG. 18 illustrates a USBD according to an embodiment of the presentinvention.

FIG. 19 illustrates an S-TSID according to an embodiment of the presentinvention.

FIG. 20 illustrates a hierarchical signaling structure according to anembodiment of the present invention.

FIG. 21 illustrates a method for transmitting EA information usingUDP/IP according to an embodiment of the present invention.

FIG. 22 illustrates a method for transmitting EA information usingUDP/IP according to an embodiment of the present invention.

FIG. 23 illustrates an EA message according to an embodiment of thepresent invention.

FIG. 24 illustrates a resource location transmitted to support theenhanced alert according to an embodiment of the present invention.

FIG. 25 illustrates a syntax representing a location of a resource foran enhanced alert transmission according to an embodiment of the presentinvention.

FIG. 26 illustrates EA information according to another embodiment ofthe present invention.

FIG. 27 illustrates an embodiment of signaling an embedded EA in an EAmessage.

FIG. 28 illustrates an embodiment of signaling an EA with a separatesession in an EA message.

FIG. 29 illustrates syntax of the EA information according to anotherembodiment of the present invention.

FIG. 30 illustrates an ENRT-IT (EA related NRT information table) forrich media contents signaling according to an embodiment of the presentinvention.

FIG. 31 illustrates a signaling structure of rich media contentsaccording to an embodiment of the present invention.

FIG. 32 is a diagram illustrating a method for waking up a broadcastreceiver or processing an EA message according to an embodiment of thepresent invention.

FIG. 33 illustrates an operation of a broadcast receiver according towake-up information.

FIG. 34 illustrates a method for transmitting a broadcast signalaccording to an embodiment of the present invention.

FIG. 35 illustrates a broadcast signal transmitter and a broadcastsignal receiver according to an embodiment of the present invention.

BEST MODE FOR INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. The detailed description, which will be given below withreference to the accompanying drawings, is intended to explain exemplaryembodiments of the present invention, rather than to show the onlyembodiments that can be implemented according to the present invention.The following detailed description includes specific details in order toprovide a thorough understanding of the present invention. However, itwill be apparent to those skilled in the art that the present inventionmay be practiced without such specific details.

Although most terms used in the present invention have been selectedfrom general ones widely used in the art, some terms have beenarbitrarily selected by the applicant and their meanings are explainedin detail in the following description as needed. Thus, the presentinvention should be understood based upon the intended meanings of theterms rather than their simple names or meanings. Also, the term blockand module are used similarly to indicate logical/functional unit ofparticular signal/data processing.

The present invention provides apparatuses and methods for transmittingand receiving broadcast signals for future broadcast services. Futurebroadcast services according to an embodiment of the present inventioninclude a terrestrial broadcast service, a mobile broadcast service, aUHDTV service, etc. The present invention may process broadcast signalsfor the future broadcast services through non-MIMO or MIMO according toone embodiment. A non-MIMO scheme according to an embodiment of thepresent invention may include a multiple input single output (MISO)scheme, a single input single output (SISO) scheme, etc. The presentinvention proposes a physical profile (or system) optimized to minimizereceiver complexity while attaining the performance required for aparticular use case.

FIG. 1 is a diagram showing a protocol stack according to an embodimentof the present invention.

A service may be delivered to a receiver through a plurality of layers.First, a transmission side may generate service data. The service datamay be processed for transmission at a delivery layer of thetransmission side and the service data may be encoded into a broadcastsignal and transmitted over a broadcast or broadband network at aphysical layer.

Here, the service data may be generated in an ISO base media file format(BMFF). ISO BMFF media files may be used for broadcast/broadband networkdelivery, media encapsulation and/or synchronization format. Here, theservice data is all data related to the service and may include servicecomponents configuring a linear service, signaling information thereof,non real time (NRT) data and other files.

The delivery layer will be described. The delivery layer may provide afunction for transmitting service data. The service data may bedelivered over a broadcast and/or broadband network.

Broadcast service delivery may include two methods.

As a first method, service data may be processed in media processingunits (MPUs) based on MPEG media transport (MMT) and transmitted usingan MMT protocol (MMTP). In this case, the service data delivered usingthe MMTP may include service components for a linear service and/orservice signaling information thereof.

As a second method, service data may be processed into DASH segments andtransmitted using real time object delivery over unidirectionaltransport (ROUTE), based on MPEG DASH. In this case, the service datadelivered through the ROUTE protocol may include service components fora linear service, service signaling information thereof and/or NRT data.That is, the NRT data and non-timed data such as files may be deliveredthrough ROUTE.

Data processed according to MMTP or ROUTE protocol may be processed intoIP packets through a UDP/IP layer. In service data delivery over thebroadcast network, a service list table (SLT) may also be delivered overthe broadcast network through a UDP/IP layer. The SLT may be deliveredin a low level signaling (LLS) table. The SLT and LLS table will bedescribed later.

IP packets may be processed into link layer packets in a link layer. Thelink layer may encapsulate various formats of data delivered from ahigher layer into link layer packets and then deliver the packets to aphysical layer. The link layer will be described later.

In hybrid service delivery, at least one service element may bedelivered through a broadband path. In hybrid service delivery, datadelivered over broadband may include service components of a DASHformat, service signaling information thereof and/or NRT data. This datamay be processed through HTTP/TCP/IP and delivered to a physical layerfor broadband transmission through a link layer for broadbandtransmission.

The physical layer may process the data received from the delivery layer(higher layer and/or link layer) and transmit the data over thebroadcast or broadband network. A detailed description of the physicallayer will be given later.

The service will be described. The service may be a collection ofservice components displayed to a user, the components may be of variousmedia types, the service may be continuous or intermittent, the servicemay be real time or non real time, and a real-time service may include asequence of TV programs.

The service may have various types. First, the service may be a linearaudio/video or audio service having app based enhancement. Second, theservice may be an app based service, reproduction/configuration of whichis controlled by a downloaded application. Third, the service may be anESG service for providing an electronic service guide (ESG). Fourth, theservice may be an emergency alert (EA) service for providing emergencyalert information.

When a linear service without app based enhancement is delivered overthe broadcast network, the service component may be delivered by (1) oneor more ROUTE sessions or (2) one or more MMTP sessions.

When a linear service having app based enhancement is delivered over thebroadcast network, the service component may be delivered by (1) one ormore ROUTE sessions or (2) zero or more MMTP sessions. In this case,data used for app based enhancement may be delivered through a ROUTEsession in the form of NRT data or other files. In one embodiment of thepresent invention, simultaneous delivery of linear service components(streaming media components) of one service using two protocols may notbe allowed.

When an app based service is delivered over the broadcast network, theservice component may be delivered by one or more ROUTE sessions. Inthis case, the service data used for the app based service may bedelivered through the ROUTE session in the form of NRT data or otherfiles.

Some service components of such a service, some NRT data, files, etc.may be delivered through broadband (hybrid service delivery).

That is, in one embodiment of the present invention, linear servicecomponents of one service may be delivered through the MMT protocol. Inanother embodiment of the present invention, the linear servicecomponents of one service may be delivered through the ROUTE protocol.In another embodiment of the present invention, the linear servicecomponents of one service and NRT data (NRT service components) may bedelivered through the ROUTE protocol. In another embodiment of thepresent invention, the linear service components of one service may bedelivered through the MMT protocol and the NRT data (NRT servicecomponents) may be delivered through the ROUTE protocol. In theabove-described embodiments, some service components of the service orsome NRT data may be delivered through broadband. Here, the app basedservice and data regarding app based enhancement may be delivered overthe broadcast network according to ROUTE or through broadband in theform of NRT data. NRT data may be referred to as locally cached data.

Each ROUTE session includes one or more LCT sessions for wholly orpartially delivering content components configuring the service. Instreaming service delivery, the LCT session may deliver individualcomponents of a user service, such as audio, video or closed captionstream. The streaming media is formatted into a DASH segment.

Each MMTP session includes one or more MMTP packet flows for deliveringall or some of content components or an MMT signaling message. The MMTPpacket flow may deliver a component formatted into MPU or an MMTsignaling message.

For delivery of an NRT user service or system metadata, the LCT sessiondelivers a file based content item. Such content files may includeconsecutive (timed) or discrete (non-timed) media components of the NRTservice or metadata such as service signaling or ESG fragments. Systemmetadata such as service signaling or ESG fragments may be deliveredthrough the signaling message mode of the MMTP.

A receiver may detect a broadcast signal while a tuner tunes tofrequencies. The receiver may extract and send an SLT to a processingmodule. The SLT parser may parse the SLT and acquire and store data in achannel map. The receiver may acquire and deliver bootstrap informationof the SLT to a ROUTE or MMT client. The receiver may acquire and storean SLS. USBD may be acquired and parsed by a signaling parser.

FIG. 2 is a diagram showing a service discovery procedure according toone embodiment of the present invention.

A broadcast stream delivered by a broadcast signal frame of a physicallayer may carry low level signaling (LLS). LLS data may be carriedthrough payload of IP packets delivered to a well-known IP address/port.This LLS may include an SLT according to type thereof. The LLS data maybe formatted in the form of an LLS table. A first byte of every UDP/IPpacket carrying the LLS data may be the start of the LLS table. Unlikethe shown embodiment, an IP stream for delivering the LLS data may bedelivered to a PLP along with other service data.

The SLT may enable the receiver to generate a service list through fastchannel scan and provides access information for locating the SLS. TheSLT includes bootstrap information. This bootstrap information mayenable the receiver to acquire service layer signaling (SLS) of eachservice. When the SLS, that is, service signaling information, isdelivered through ROUTE, the bootstrap information may include an LCTchannel carrying the SLS, a destination IP address of a ROUTE sessionincluding the LCT channel and destination port information. When the SLSis delivered through the MMT, the bootstrap information may include adestination IP address of an MMTP session carrying the SLS anddestination port information.

In the shown embodiment, the SLS of service #1 described in the SLT isdelivered through ROUTE and the SLT may include bootstrap informationsIP1, dIP1 and dPort1 of the ROUTE session including the LCT channeldelivered by the SLS. The SLS of service #2 described in the SLT isdelivered through MMT and the SLT may include bootstrap informationsIP2, dIP2 and dPort2 of the MMTP session including the MMTP packet flowdelivered by the SLS.

The SLS is signaling information describing the properties of theservice and may include receiver capability information forsignificantly reproducing the service or providing information foracquiring the service and the service component of the service. Wheneach service has separate service signaling, the receiver acquiresappropriate SLS for a desired service without parsing all SLSs deliveredwithin a broadcast stream.

When the SLS is delivered through the ROUTE protocol, the SLS may bedelivered through a dedicated LCT channel of a ROUTE session indicatedby the SLT. In some embodiments, this LCT channel may be an LCT channelidentified by tsi=0. In this case, the SLS may include a user servicebundle description (USBD)/user service description (USD), service-basedtransport session instance description (S-TSID) and/or mediapresentation description (MPD).

Here, USBD/USD is one of SLS fragments and may serve as a signaling hubdescribing detailed description information of a service. The USBD mayinclude service identification information, device capabilityinformation, etc. The USBD may include reference information (URIreference) of other SLS fragments (S-TSID, MPD, etc.). That is, theUSBD/USD may reference the S-TSID and the MPD. In addition, the USBD mayfurther include metadata information for enabling the receiver to decidea transmission mode (broadcast/broadband network). A detaileddescription of the USBD/USD will be given below.

The S-TSID is one of SLS fragments and may provide overall sessiondescription information of a transport session carrying the servicecomponent of the service. The S-TSID may provide the ROUTE sessionthrough which the service component of the service is delivered and/ortransport session description information for the LCT channel of theROUTE session. The S-TSID may provide component acquisition informationof service components associated with one service. The S-TSID mayprovide mapping between DASH representation of the MPD and the tsi ofthe service component. The component acquisition information of theS-TSID may be provided in the form of the identifier of the associatedDASH representation and tsi and may or may not include a PLP ID in someembodiments. Through the component acquisition information, the receivermay collect audio/video components of one service and perform bufferingand decoding of DASH media segments. The S-TSID may be referenced by theUSBD as described above. A detailed description of the S-TSID will begiven below.

The MPD is one of SLS fragments and may provide a description of DASHmedia presentation of the service. The MPD may provide a resourceidentifier of media segments and provide context information within themedia presentation of the identified resources. The MPD may describeDASH representation (service component) delivered over the broadcastnetwork and describe additional DASH presentation delivered overbroadband (hybrid delivery). The MPD may be referenced by the USBD asdescribed above.

When the SLS is delivered through the MMT protocol, the SLS may bedelivered through a dedicated MMTP packet flow of the MMTP sessionindicated by the SLT. In some embodiments, the packet_id of the MMTPpackets delivering the SLS may have a value of 00. In this case, the SLSmay include a USBD/USD and/or MMT packet (MP) table.

Here, the USBD is one of SLS fragments and may describe detaileddescription information of a service as in ROUTE. This USBD may includereference information (URI information) of other SLS fragments. The USBDof the MMT may reference an MP table of MMT signaling. In someembodiments, the USBD of the MMT may include reference information ofthe S-TSID and/or the MPD. Here, the S-TSID is for NRT data deliveredthrough the ROUTE protocol. Even when a linear service component isdelivered through the MMT protocol, NRT data may be delivered via theROUTE protocol. The MPD is for a service component delivered overbroadband in hybrid service delivery. The detailed description of theUSBD of the MMT will be given below.

The MP table is a signaling message of the MMT for MPU components andmay provide overall session description information of an MMTP sessioncarrying the service component of the service. In addition, the MP tablemay include a description of an asset delivered through the MMTPsession. The MP table is streaming signaling information for MPUcomponents and may provide a list of assets corresponding to one serviceand location information (component acquisition information) of thesecomponents. The detailed description of the MP table may be defined inthe MMT or modified. Here, the asset is a multimedia data entity, iscombined by one unique ID, and may mean a data entity used to onemultimedia presentation. The asset may correspond to service componentsconfiguring one service. A streaming service component (MPU)corresponding to a desired service may be accessed using the MP table.The MP table may be referenced by the USBD as described above.

The other MMT signaling messages may be defined. Additional informationassociated with the service and the MMTP session may be described bysuch MMT signaling messages.

The ROUTE session is identified by a source IP address, a destination IPaddress and a destination port number. The LCT session is identified bya unique transport session identifier (TSI) within the range of a parentROUTE session. The MMTP session is identified by a destination IPaddress and a destination port number. The MMTP packet flow isidentified by a unique packet_id within the range of a parent MMTPsession.

In case of ROUTE, the S-TSID, the USBD/USD, the MPD or the LCT sessiondelivering the same may be referred to as a service signaling channel.In case of MMTP, the USBD/UD, the MMT signaling message or the packetflow delivering the same may be referred to as a service signalingchannel.

Unlike the shown embodiment, one ROUTE or MMTP session may be deliveredover a plurality of PLPs. That is, one service may be delivered throughone or more PLPs. Unlike the shown embodiment, in some embodiments,components configuring one service may be delivered through differentROUTE sessions. In addition, in some embodiments, components configuringone service may be delivered through different MMTP sessions. In someembodiments, components configuring one service may be divided anddelivered in a ROUTE session and an MMTP session. Although not shown,components configuring one service may be delivered through broadband(hybrid delivery).

FIG. 3 is a diagram showing a low level signaling (LLS) table and aservice list table (SLT) according to one embodiment of the presentinvention.

One embodiment t3010 of the LLS table may include information accordingto an LLS_table_id field, a provider_id field, an LLS_table_versionfield and/or an LLS_table_id field.

The LLS_table_id field may identify the type of the LLS table, and theprovider_id field may identify a service provider associated withservices signaled by the LLS table. Here, the service provider is abroadcaster using all or some of the broadcast streams and theprovider_id field may identify one of a plurality of broadcasters whichis using the broadcast streams. The LLS_table_version field may providethe version information of the LLS table.

According to the value of the LLS_table_id field, the LLS table mayinclude one of the above-described SLT, a rating region table (RRT)including information on a content advisory rating, SystemTimeinformation for providing information associated with a system time, acommon alert protocol (CAP) message for providing information associatedwith emergency alert. In some embodiments, the other information may beincluded in the LLS table.

One embodiment t3020 of the shown SLT may include an @bsid attribute, an@sltCapabilities attribute, an sltInetUrl element and/or a Serviceelement. Each field may be omitted according to the value of the shownUse column or a plurality of fields may be present.

The @bsid attribute may be the identifier of a broadcast stream. The@sltCapabilities attribute may provide capability information requiredto decode and significantly reproduce all services described in the SLT.The sltInetUrl element may provide base URL information used to obtainservice signaling information and ESG for the services of the SLT overbroadband. The sltInetUrl element may further include an @urlTypeattribute, which may indicate the type of data capable of being obtainedthrough the URL.

The Service element may include information on services described in theSLT, and the Service element of each service may be present. The Serviceelement may include an @serviceID attribute, an @sltSvcSeqNum attribute,an @protected attribute, an @majorChannelNo attribute, an@minorChannelNo attribute, an @serviceCategory attribute, an@shortServiceName attribute, an @hidden attribute, an@broadbandAccessRequired attribute, an @svcCapabilities attribute, aBroadcastSvcSignaling element and/or an svcInetUrl element.

The @serviceID attribute is the identifier of the service and the@sltSvcSeqNum attribute may indicate the sequence number of the SLTinformation of the service. The @protected attribute may indicatewhether at least one service component necessary for significantreproduction of the service is protected. The @majorChannelNo attributeand the @minorChannelNo attribute may indicate the major channel numberand minor channel number of the service, respectively.

The @serviceCategory attribute may indicate the category of the service.The category of the service may include a linear A/V service, a linearaudio service, an app based service, an ESG service, an EAS service,etc. The @shortServiceName attribute may provide the short name of theservice. The @hidden attribute may indicate whether the service is fortesting or proprietary use. The @broadbandAccessRequired attribute mayindicate whether broadband access is necessary for significantreproduction of the service. The @svcCapabilities attribute may providecapability information necessary for decoding and significantreproduction of the service.

The BroadcastSvcSignaling element may provide information associatedwith broadcast signaling of the service. This element may provideinformation such as location, protocol and address with respect tosignaling over the broadcast network of the service. Details thereofwill be described below.

The svcInetUrl element may provide URL information for accessing thesignaling information of the service over broadband. The sltInetUrlelement may further include an @urlType attribute, which may indicatethe type of data capable of being obtained through the URL.

The above-described BroadcastSvcSignaling element may include an@slsProtocol attribute, an @slsMajorProtocolVersion attribute, an@slsMinorProtocolVersion attribute, an @slsPlpId attribute, an@slsDestinationIpAddress attribute, an @slsDestinationUdpPort attributeand/or an @slsSourceIpAddress attribute.

The @slsProtocol attribute may indicate the protocol used to deliver theSLS of the service (ROUTE, MMT, etc.). The @slsMajorProtocolVersionattribute and the @slsMinorProtocolVersion attribute may indicate themajor version number and minor version number of the protocol used todeliver the SLS of the service, respectively.

The @slsPlpId attribute may provide a PLP identifier for identifying thePLP delivering the SLS of the service. In some embodiments, this fieldmay be omitted and the PLP information delivered by the SLS may bechecked using a combination of the information of the below-describedLMT and the bootstrap information of the SLT.

The @slsDestinationIpAddress attribute, the @slsDestinationUdpPortattribute and the @slsSourceIpAddress attribute may indicate thedestination IP address, destination UDP port and source IP address ofthe transport packets delivering the SLS of the service, respectively.These may identify the transport session (ROUTE session or MMTP session)delivered by the SLS. These may be included in the bootstrapinformation.

FIG. 4 is a diagram showing a USBD and an S-TSID delivered through ROUTEaccording to one embodiment of the present invention.

One embodiment t4010 of the shown USBD may have a bundleDescription rootelement. The bundleDescription root element may have auserServiceDescription element. The userServiceDescription element maybe an instance of one service.

The userServiceDescription element may include an @globalServiceIDattribute, an @serviceId attribute, an @serviceStatus attribute, an@fullMPDUri attribute, an @sTSIDUri attribute, a name element, aserviceLanguage element, a capabilityCode element and/or adeliveryMethod element. Each field may be omitted according to the valueof the shown Use column or a plurality of fields may be present.

The @globalServiceID attribute is the globally unique identifier of theservice and may be used for link with ESG data(Service@globalServiceID). The @serviceId attribute is a referencecorresponding to the service entry of the SLT and may be equal to theservice ID information of the SLT. The @serviceStatus attribute mayindicate the status of the service. This field may indicate whether theservice is active or inactive.

The @fullMPDUri attribute may reference the MPD fragment of the service.The MPD may provide a reproduction description of a service componentdelivered over the broadcast or broadband network as described above.The @sTSIDUri attribute may reference the S-TSID fragment of theservice. The S-TSID may provide parameters associated with access to thetransport session carrying the service as described above.

The name element may provide the name of the service. This element mayfurther include an @lang attribute and this field may indicate thelanguage of the name provided by the name element. The serviceLanguageelement may indicate available languages of the service. That is, thiselement may arrange the languages capable of being provided by theservice.

The capabilityCode element may indicate capability or capability groupinformation of a receiver necessary to significantly reproduce theservice. This information is compatible with capability informationformat provided in service announcement.

The deliveryMethod element may provide transmission related informationwith respect to content accessed over the broadcast or broadband networkof the service. The deliveryMethod element may include abroadcastAppService element and/or a unicastAppService element. Each ofthese elements may have a basePattern element as a sub element.

The broadcastAppService element may include transmission associatedinformation of the DASH representation delivered over the broadcastnetwork. The DASH representation may include media components over allperiods of the service presentation.

The basePattern element of this element may indicate a character patternused for the receiver to perform matching with the segment URL. This maybe used for a DASH client to request the segments of the representation.Matching may imply delivery of the media segment over the broadcastnetwork.

The unicastAppService element may include transmission relatedinformation of the DASH representation delivered over broadband. TheDASH representation may include media components over all periods of theservice media presentation.

The basePattern element of this element may indicate a character patternused for the receiver to perform matching with the segment URL. This maybe used for a DASH client to request the segments of the representation.Matching may imply delivery of the media segment over broadband.

One embodiment t4020 of the shown S-TSID may have an S-TSID rootelement. The S-TSID root element may include an @serviceId attributeand/or an RS element. Each field may be omitted according to the valueof the shown Use column or a plurality of fields may be present.

The @serviceId attribute is the identifier of the service and mayreference the service of the USBD/USD. The RS element may describeinformation on ROUTE sessions through which the service components ofthe service are delivered. According to the number of ROUTE sessions, aplurality of elements may be present. The RS element may further includean @bsid attribute, an @sIpAddr attribute, an @dIpAddr attribute, an@dport attribute, an @PLPID attribute and/or an LS element.

The @bsid attribute may be the identifier of a broadcast stream in whichthe service components of the service are delivered. If this field isomitted, a default broadcast stream may be a broadcast stream includingthe PLP delivering the SLS of the service. The value of this field maybe equal to that of the @bsid attribute.

The @sIpAddr attribute, the @dIpAddr attribute and the @dport attributemay indicate the source IP address, destination IP address anddestination UDP port of the ROUTE session, respectively. When thesefields are omitted, the default values may be the source address,destination IP address and destination UDP port values of the currentROUTE session delivering the SLS, that is, the S-TSID. This field maynot be omitted in another ROUTE session delivering the servicecomponents of the service, not in the current ROUTE session.

The @PLPID attribute may indicate the PLP ID information of the ROUTEsession. If this field is omitted, the default value may be the PLP IDvalue of the current PLP delivered by the S-TSID. In some embodiments,this field is omitted and the PLP ID information of the ROUTE sessionmay be checked using a combination of the information of thebelow-described LMT and the IP address/UDP port information of the RSelement.

The LS element may describe information on LCT channels through whichthe service components of the service are transmitted. According to thenumber of LCT channel, a plurality of elements may be present. The LSelement may include an @tsi attribute, an @PLPID attribute, an @bwattribute, an @startTime attribute, an @endTime attribute, a SrcFlowelement and/or a RepairFlow element.

The @tsi attribute may indicate the tsi information of the LCT channel.Using this, the LCT channels through which the service components of theservice are delivered may be identified. The @PLPID attribute mayindicate the PLP ID information of the LCT channel. In some embodiments,this field may be omitted. The @bw attribute may indicate the maximumbandwidth of the LCT channel. The @startTime attribute may indicate thestart time of the LCT session and the @endTime attribute may indicatethe end time of the LCT channel.

The SrcFlow element may describe the source flow of ROUTE. The sourceprotocol of ROUTE is used to transmit a delivery object and at least onesource flow may be established within one ROUTE session. The source flowmay deliver associated objects as an object flow.

The RepairFlow element may describe the repair flow of ROUTE. Deliveryobjects delivered according to the source protocol may be protectedaccording to forward error correction (FEC) and the repair protocol maydefine an FEC framework enabling FEC protection.

FIG. 5 is a diagram showing a USBD delivered through MMT according toone embodiment of the present invention.

One embodiment of the shown USBD may have a bundleDescription rootelement. The bundleDescription root element may have auserServiceDescription element. The userServiceDescription element maybe an instance of one service.

The userServiceDescription element may include an @globalServiceIDattribute, an @serviceId attribute, a Name element, a serviceLanguageelement, a contentAdvisoryRating element, a Channel element, ampuComponent element, a routeComponent element, a broadbandComponentelement and/or a ComponentInfo element. Each field may be omittedaccording to the value of the shown Use column or a plurality of fieldsmay be present.

The @globalServiceID attribute, the @serviceId attribute, the Nameelement and/or the serviceLanguage element may be equal to the fields ofthe USBD delivered through ROUTE. The contentAdvisoryRating element mayindicate the content advisory rating of the service. This information iscompatible with content advisory rating information format provided inservice announcement. The Channel element may include informationassociated with the service. A detailed description of this element willbe given below.

The mpuComponent element may provide a description of service componentsdelivered as the MPU of the service. This element may further include an@mmtPackageId attribute and/or an @nextMmtPackageId attribute. The@mmtPackageId attribute may reference the MMT package of the servicecomponents delivered as the MPU of the service. The @nextMmtPackageIdattribute may reference an MMT package to be used after the MMT packagereferenced by the @mmtPackageId attribute in terms of time. Through theinformation of this element, the MP table may be referenced.

The routeComponent element may include a description of the servicecomponents of the service. Even when linear service components aredelivered through the MMT protocol, NRT data may be delivered accordingto the ROUTE protocol as described above. This element may describeinformation on such NRT data. A detailed description of this elementwill be given below.

The broadbandComponent element may include the description of theservice components of the service delivered over broadband. In hybridservice delivery, some service components of one service or other filesmay be delivered over broadband. This element may describe informationon such data. This element may further an @fullMPDUri attribute. Thisattribute may reference the MPD describing the service componentdelivered over broadband. In addition to hybrid service delivery, thebroadcast signal may be weakened due to traveling in a tunnel and thusthis element may be necessary to support handoff between broadband andbroadband. When the broadcast signal is weak, the service component isacquired over broadband and, when the broadcast signal becomes strong,the service component is acquired over the broadcast network to secureservice continuity.

The ComponentInfo element may include information on the servicecomponents of the service. According to the number of service componentsof the service, a plurality of elements may be present. This element maydescribe the type, role, name, identifier or protection of each servicecomponent. Detailed information of this element will be described below.

The above-described Channel element may further include an @serviceGenreattribute, an @serviceIcon attribute and/or a ServiceDescriptionelement. The @serviceGenre attribute may indicate the genre of theservice and the @serviceIcon attribute may include the URL informationof the representative icon of the service. The ServiceDescriptionelement may provide the service description of the service and thiselement may further include an @serviceDescrText attribute and/or an@serviceDescrLang attribute. These attributes may indicate the text ofthe service description and the language used in the text.

The above-described routeComponent element may further include an@sTSIDUri attribute, an @sTSIDDestinationIpAddress attribute, an@sTSIDDestinationUdpPort attribute, an @sTSIDSourceIpAddress attribute,an @sTSIDMajorProtocolVersion attribute and/or an@sTSIDMinorProtocolVersion attribute.

The @sTSIDUri attribute may reference an S-TSID fragment. This field maybe equal to the field of the USBD delivered through ROUTE. This S-TSIDmay provide access related information of the service componentsdelivered through ROUTE. This S-TSID may be present for NRT datadelivered according to the ROUTE protocol in a state of deliveringlinear service component according to the MMT protocol.

The @sTSIDDestinationIpAddress attribute, the @sTSIDDestinationUdpPortattribute and the @sTSIDSourceIpAddress attribute may indicate thedestination IP address, destination UDP port and source IP address ofthe transport packets carrying the above-described S-TSID. That is,these fields may identify the transport session (MMTP session or theROUTE session) carrying the above-described S-TSID.

The @sTSIDMajorProtocolVersion attribute and the@sTSIDMinorProtocolVersion attribute may indicate the major versionnumber and minor version number of the transport protocol used todeliver the above-described S-TSID, respectively.

The above-described ComponentInfo element may further include an@componentType attribute, an @componentRole attribute, an@componentProtectedFlag attribute, an @componentId attribute and/or an@componentName attribute.

The @componentType attribute may indicate the type of the component. Forexample, this attribute may indicate whether the component is an audio,video or closed caption component. The @componentRole attribute mayindicate the role of the component. For example, this attribute mayindicate main audio, music, commentary, etc. if the component is anaudio component. This attribute may indicate primary video if thecomponent is a video component. This attribute may indicate a normalcaption or an easy reader type if the component is a closed captioncomponent.

The @componentProtectedFlag attribute may indicate whether the servicecomponent is protected, for example, encrypted. The @componentIdattribute may indicate the identifier of the service component. Thevalue of this attribute may be the asset_id (asset ID) of the MP tablecorresponding to this service component. The @componentName attributemay indicate the name of the service component.

FIG. 6 is a diagram showing link layer operation according to oneembodiment of the present invention.

The link layer may be a layer between a physical layer and a networklayer. A transmission side may transmit data from the network layer tothe physical layer and a reception side may transmit data from thephysical layer to the network layer (t6010). The purpose of the linklayer is to compress (abstract) all input packet types into one formatfor processing by the physical layer and to secure flexibility andexpandability of an input packet type which is not defined yet. Inaddition, the link layer may provide option for compressing(abstracting) unnecessary information of the header of input packets toefficiently transmit input data. Operation such as overhead reduction,encapsulation, etc. of the link layer is referred to as a link layerprotocol and packets generated using this protocol may be referred to aslink layer packets. The link layer may perform functions such as packetencapsulation, overhead reduction and/or signaling transmission.

At the transmission side, the link layer (ALP) may perform an overheadreduction procedure with respect to input packets and then encapsulatethe input packets into link layer packets. In addition, in someembodiments, the link layer may perform encapsulation into the linklayer packets without performing the overhead reduction procedure. Dueto use of the link layer protocol, data transmission overhead on thephysical layer may be significantly reduced and the link layer protocolaccording to the present invention may provide IP overhead reductionand/or MPEG-2 TS overhead reduction.

When the shown IP packets are input as input packets (t6010), the linklayer may sequentially perform IP header compression, adaptation and/orencapsulation. In some embodiments, some processes may be omitted. Forexample, the RoHC module may perform IP packet header compression toreduce unnecessary overhead. Context information may be extractedthrough the adaptation procedure and transmitted out of band. The IPheader compression and adaption procedure may be collectively referredto as IP header compression. Thereafter, the IP packets may beencapsulated into link layer packets through the encapsulationprocedure.

When MPEG 2 TS packets are input as input packets, the link layer maysequentially perform overhead reduction and/or an encapsulationprocedure with respect to the TS packets. In some embodiments, someprocedures may be omitted. In overhead reduction, the link layer mayprovide sync byte removal, null packet deletion and/or common headerremoval (compression). Through sync byte removal, overhead reduction of1 byte may be provided per TS packet. Null packet deletion may beperformed in a manner in which reinsertion is possible at the receptionside. In addition, deletion (compression) may be performed in a mannerin which common information between consecutive headers may be restoredat the reception side. Some of the overhead reduction procedures may beomitted. Thereafter, through the encapsulation procedure, the TS packetsmay be encapsulated into link layer packets. The link layer packetstructure for encapsulation of the TS packets may be different from thatof the other types of packets.

First, IP header compression will be described.

The IP packets may have a fixed header format but some informationnecessary for a communication environment may be unnecessary for abroadcast environment. The link layer protocol may compress the headerof the IP packet to provide a mechanism for reducing broadcast overhead.

IP header compression may employ a header compressor/decompressor and/oran adaptation module. The IP header compressor (RoHC compressor) mayreduce the size of each IP packet header based on the RoHC scheme.Thereafter, the adaptation module may extract context information andgenerate signaling information from each packet stream. A receiver mayparse signaling information associated with the packet stream and attachcontext information to the packet stream. The RoHC decompressor mayrestore the packet header to reconfigure an original IP packet.Hereinafter, IP header compression may mean only IP header compressionby a header compression or a combination of IP header compression and anadaptation process by an adaptation module. The same is true indecompressing.

Hereinafter, adaptation will be described.

In transmission of a single-direction link, when the receiver does nothave context information, the decompressor cannot restore the receivedpacket header until complete context is received. This may lead tochannel change delay and turn-on delay. Accordingly, through theadaptation function, configuration parameters and context informationbetween the compressor and the decompressor may be transmitted out ofband. The adaptation function may provide construction of link layersignaling using context information and/or configuration parameters. Theadaptation function may use previous configuration parameters and/orcontext information to periodically transmit link layer signalingthrough each physical frame.

Context information is extracted from the compressed IP packets andvarious methods may be used according to adaptation mode.

Mode #1 refers to a mode in which no operation is performed with respectto the compressed packet stream and an adaptation module operates as abuffer.

Mode #2 refers to a mode in which an IR packet is detected from acompressed packet stream to extract context information (static chain).After extraction, the IR packet is converted into an IR-DYN packet andthe IR-DYN packet may be transmitted in the same order within the packetstream in place of an original IR packet.

Mode #3 (t6020) refers to a mode in which IR and IR-DYN packets aredetected from a compressed packet stream to extract context information.A static chain and a dynamic chain may be extracted from the IR packetand a dynamic chain may be extracted from the IR-DYN packet. Afterextraction, the IR and IR-DYN packets are converted into normalcompression packets. The converted packets may be transmitted in thesame order within the packet stream in place of original IR and IR-DYNpackets.

In each mode, the context information is extracted and the remainingpackets may be encapsulated and transmitted according to the link layerpacket structure for the compressed IP packets. The context informationmay be encapsulated and transmitted according to the link layer packetstructure for signaling information, as link layer signaling.

The extracted context information may be included in a RoHC-Udescription table (RDT) and may be transmitted separately from the RoHCpacket flow. Context information may be transmitted through a specificphysical data path along with other signaling information. The specificphysical data path may mean one of normal PLPs, a PLP in which low levelsignaling (LLS) is delivered, a dedicated PLP or an L1 signaling path.Here, the RDT may be context information (static chain and/or dynamicchain) and/or signaling information including information associatedwith header compression. In some embodiments, the RDT shall betransmitted whenever the context information is changed. In addition, insome embodiments, the RDT shall be transmitted every physical frame. Inorder to transmit the RDT every physical frame, the previous RDT may bereused.

The receiver may select a first PLP and first acquire signalinginformation of the SLT, the RDT, the LMT, etc., prior to acquisition ofa packet stream. When signaling information is acquired, the receivermay combine the signaling information to acquire mapping betweenservice—IP information—context information—PLP. That is, the receivermay check which service is transmitted in which IP streams or which IPstreams are delivered in which PLP and acquire context information ofthe PLPs. The receiver may select and decode a PLP carrying a specificpacket stream. The adaptation module may parse context information andcombine the context information with the compressed packets. To thisend, the packet stream may be restored and delivered to the RoHCdecompressor. Thereafter, decompression may start. At this time, thereceiver may detect IR packets to start decompression from an initiallyreceived IR packet (mode 1), detect IR-DYN packets to startdecompression from an initially received IR-DYN packet (mode 2) or startdecompression from any compressed packet (mode 3).

Hereinafter, packet encapsulation will be described.

The link layer protocol may encapsulate all types of input packets suchas IP packets, TS packets, etc. into link layer packets. To this end,the physical layer processes only one packet format independently of theprotocol type of the network layer (here, an MPEG-2 TS packet isconsidered as a network layer packet). Each network layer packet orinput packet is modified into the payload of a generic link layerpacket.

In the packet encapsulation procedure, segmentation may be used. If thenetwork layer packet is too large to be processed in the physical layer,the network layer packet may be segmented into two or more segments. Thelink layer packet header may include fields for segmentation of thetransmission side and recombination of the reception side. Each segmentmay be encapsulated into the link layer packet in the same order as theoriginal location.

In the packet encapsulation procedure, concatenation may also be used.If the network layer packet is sufficiently small such that the payloadof the link layer packet includes several network layer packets,concatenation may be performed. The link layer packet header may includefields for performing concatenation. In concatenation, the input packetsmay be encapsulated into the payload of the link layer packet in thesame order as the original input order.

The link layer packet may include a header and a payload. The header mayinclude a base header, an additional header and/or an optional header.The additional header may be further added according to situation suchas concatenation or segmentation and the additional header may includefields suitable for situations. In addition, for delivery of theadditional information, the optional header may be further included.Each header structure may be predefined. As described above, if theinput packets are TS packets, a link layer header having packetsdifferent from the other packets may be used.

Hereinafter, link layer signaling will be described.

Link layer signaling may operate at a level lower than that of the IPlayer. The reception side may acquire link layer signaling faster thanIP level signaling of the LLS, the SLT, the SLS, etc. Accordingly, linklayer signaling may be acquired before session establishment.

Link layer signaling may include internal link layer signaling andexternal link layer signaling. Internal link layer signaling may besignaling information generated at the link layer. This includes theabove-described RDT or the below-described LMT. External link layersignaling may be signaling information received from an external module,an external protocol or a higher layer. The link layer may encapsulatelink layer signaling into a link layer packet and deliver the link layerpacket. A link layer packet structure (header structure) for link layersignaling may be defined and link layer signaling information may beencapsulated according to this structure.

FIG. 7 is a diagram showing a link mapping table (LMT) according to oneembodiment of the present invention.

The LMT may provide a list of higher layer sessions carried through thePLP. In addition, the LMT may provide additional information forprocessing link layer packets carrying the higher layer sessions. Here,the higher layer session may also be referred to as multicast.Information on IP streams or transport sessions transmitted through aspecific PLP may be acquired through the LMT. In contrast, informationon through which PLP a specific transport session is delivered may beacquired.

The LMT may be delivered in any PLP identified as carrying LLS. Here,the PLP in which the LLS is delivered may be identified by an LLS flagof L1 detail signaling information of a physical layer. The LLS flag maybe a flag field indicating whether the LLS is delivered in the PLP, eachPLP. Here, L1 detail signaling information may correspond to thebelow-described PLS2 data.

That is, the LMT may be delivered in the same PLP along with the LLS.Each LMT shall describe mapping between PLPs and IP addresses/ports asdescribed above. As described above, the LLS may include an SLT and theIP address/port described in the LMT may be any IP address/portassociated with any service described in the SLT delivered in the samePLP as the LMT.

In some embodiments, the PLP identifier information in theabove-described SLT, SLS, etc. may be used to confirm informationindicating through which PLP a specific transport session indicated bythe SLT or SLS is transmitted may be confirmed.

In another embodiment, the PLP identifier information in theabove-described SLT, SLS, etc. will be omitted and PLP information ofthe specific transport session indicated by the SLT or SLS may beconfirmed by referring to the information in the LMT. In this case, thereceiver may combine the LMT and other IP level signaling information toidentify the PLP. Even in this embodiment, the PLP information in theSLT, SLS, etc. is not omitted and may remain in the SLT, SLS, etc.

The LMT according to the shown embodiment may include a signaling_typefield, a PLP_ID field, a num_session field and/or information on eachsession. Although the LMT of the shown embodiment describes IP streamstransmitted through one PLP, a PLP loop may be added to the LMT todescribe information on a plurality of PLPs in some embodiments. In thiscase, the LMT may describe, in a PLP loop, PLPs for any IP address/portassociated with any service described in the SLT delivered together, asdescribed above.

The signaling_type field may indicate the type of signaling informationdelivered by the table. The value of signaling_type field for the LMTmay be set to 0x01. The signaling_type field may be omitted. The PLP_IDfield may identify a target PLP to be described. If the PLP loop isused, each PLP_ID field may identify each target PLP. The PLP_ID fieldand subsequent fields thereof may be included in the PLP loop. Thebelow-described PLP_ID field is an identifier for one PLP of the PLPloop and the below-described fields may be fields for the correspondingPLP.

The num_session field may indicate the number of higher layer sessionsdelivered through the PLP identified by the corresponding PLP_ID field.

According to the number indicated by the num_session field, informationon each session may be included. This information may include asrc_IP_add field, a dst_IP_add field, a src_UDP_port field, adst_UDP_port field, an SID_flag field, a compressed_flag field, an SIDfield and/or a context_id field.

The src_IP_add field, the dst_IP_add field, the src_UDP_port field andthe dst_UDP_port field may indicate the source IP address, thedestination IP address, the source UDP port and the destination UDP portof the transport session among the higher layer sessions deliveredthrough the PLP identified by the corresponding PLP_ID field.

The SID_flag field may indicate whether the link layer packet deliveringthe transport session has an SID field in the optional header. The linklayer packet delivering the higher layer session may have an SID fieldin the optional header and the SID field value may be equal to that ofthe SID field in the LMT.

The compressed_flag field may indicate whether header compression isapplied to the data of the link layer packet delivering the transportsession. In addition, presence/absence of the below-described context_idfield may be determined according to the value of this field. If headercompression is applied (compressed_flag=1), the RDT may be present andthe PLP ID field of the RDT may have the same value as the PLP_ID fieldassociated with this compressed_flag field.

The SID field may indicate the SIDs (sub stream IDs) of the link layerpackets delivering the transport session. These link layer packets mayinclude SIDs having the same values as this SID field in the optionalheader thereof. To this end, the receiver may filter link layer packetsusing LMT information and the SID information of the link layer packetheader, without parsing all link layer packets.

The context_id field may provide a reference for a context id (CID) inthe RDT. The CID information of the RDT may indicate the context ID ofthe compression IP packet stream. The RDT may provide contextinformation of the compression IP packet stream. Through this field, theRDT and the LMT may be associated.

In the above-described embodiments of the signaling information/table ofthe present invention, the fields, elements or attributes may be omittedor may be replaced with other fields. In some embodiments, additionalfields, elements or attributes may be added.

In one embodiment of the present invention, service components of oneservice may be delivered through a plurality of ROUTE sessions. In thiscase, an SLS may be acquired through bootstrap information of an SLT. AnS-TSID and an MPD may be referenced through the USBD of the SLS. TheS-TSID may describe not only the ROUTE session delivered by the SLS butalso transport session description information of another ROUTE sessioncarried by the service components. To this end, the service componentsdelivered through the plurality of ROUTE sessions may all be collected.This is similarly applicable to the case in which the service componentsof one service are delivered through a plurality of MMTP sessions. Forreference, one service component may be simultaneously used by theplurality of services.

In another embodiment of the present invention, bootstrapping of an ESGservice may be performed by a broadcast or broadband network. Byacquiring the ESG over broadband, URL information of the SLT may beused. ESG information may be requested using this URL.

In another embodiment of the present invention, one service component ofone service may be delivered over the broadcast network and the otherservice component may be delivered over broadband (hybrid). The S-TSIDmay describe components delivered over the broadcast network such thatthe ROUTE client acquires desired service components. In addition, theUSBD may have base pattern information to describe which segments (whichcomponents) are delivered through which path. Accordingly, the receivercan confirm a segment to be requested from the broadband service and asegment to be detected in a broadcast stream.

In another embodiment of the present invention, scalable coding of aservice may be performed. The USBD may have all capability informationnecessary to render the service. For example, when one service isprovided in HD or UHD, the capability information of the USBD may have avalue of “HD or UHD”. The receiver may check which component isreproduced in order to render the UHD or HD service using the MPD.

In another embodiment of the present invention, through a TOI field ofthe LCT packets delivered through the LCT channel delivering the SLS,which SLS fragment is delivered using the LCT packets (USBD, S-TSID,MPD, etc.) may be identified.

In another embodiment of the present invention, app components to beused for app based enhancement/an app based service may be deliveredover the broadcast network as NRT components or may be delivered overbroadband. In addition, app signaling for app based enhancement may beperformed by an application signaling table (AST) delivered along withthe SLS. In addition, an event which is signaling for operation to beperformed by the app may be delivered in the form of an event messagetable (EMT) along with the SLS, may be signaled in the MPD or may bein-band signaled in the form of a box within DASH representation. TheAST, the EMT, etc. may be delivered over broadband. App basedenhancement, etc. may be provided using the collected app components andsuch signaling information.

In another embodiment of the present invention, a CAP message may beincluded and provided in the above-described LLS table for emergencyalert. Rich media content for emergency alert may also be provided. Richmedia may be signaled by a CAP message and, if rich media is present,the rich media may be provided as an EAS service signaled by the SLT.

In another embodiment of the present invention, linear servicecomponents may be delivered over the broadcast network according to theMMT protocol. In this case, NRT data (e.g., app components) of theservice may be delivered over the broadcast network according to theROUTE protocol. In addition, the data of the service may be deliveredover broadband. The receiver may access the MMTP session delivering theSLS using the bootstrap information of the SLT. The USBD of the SLSaccording to the MMT may reference the MP table such that the receiveracquires linear service components formatted into the MPU deliveredaccording to the MMT protocol. In addition, the USBD may furtherreference the S-TSID such that the receiver acquires NRT data deliveredaccording to the ROUTE protocol. In addition, the USBD may furtherreference the MPD to provide a reproduction description of datadelivered over broadband.

In another embodiment of the present invention, the receiver may deliverlocation URL information capable of acquiring a file content item (file,etc.) and/or a streaming component to a companion device through a websocket method. The application of the companion device may acquirecomponents, data, etc. through a request through HTTP GET using thisURL. In addition, the receiver may deliver information such as systemtime information, emergency alert information, etc. to the companiondevice.

FIG. 8 illustrates a configuration of a broadcast signal transmissionapparatus for future broadcast services according to an embodiment ofthe present invention.

The broadcast signal transmission apparatus for future broadcastservices according to the present embodiment may include an inputformatting block 1000, a bit interleaved coding & modulation (BICM)block 1010, a frame buidling block 1020, an OFDM generation block 1030and a signaling generation block 1040. Description will be given of anoperation of each block of the broadcast signal transmission apparatus.

In input data according to an embodiment of the present invention, IPstream/packets and MPEG2-TS may be main input formats, and other streamtypes are handled as general streams.

The input formatting block 1000 may demultiplex each input stream intoone or a plurality of data pipes, to each of which independent codingand modulation are applied. A DP is the basic unit for robustnesscontrol, which affects QoS. One or a plurality of services or servicecomponents may be carried by one DP. The DP is a logical channel in aphysical layer for delivering service data or related metadata capableof carrying one or a plurality of services or service components.

Since QoS depends on characteristics of a service provided by thebroadcast signal transmission apparatus for future broadcast servicesaccording to the embodiment of the present invention, data correspondingto respective services needs to be processed using different schemes.

BICM block 1010 may include a processing block for a profile (or system)to which MIMO is not applied, and a processing block for a profile (orsystem) to which MIMO is applied and may comprise a plurality blocks forprocessing each Data Pipe.

A processing block of the BICM block to which MIMO is not applied mayinclude a data FEC encoder, a bit interleaver, a constellation mapper, asignal space diversity (SSD) encoding block and a time interleaver. Aprocessing block of the BICM block to which MIMO is applied may isdistinguished from the processing block of the BICM block to which MIMOis not applied in that the processing block further includes a cell-worddemultiplexer and a MIMO encoding block

The data FEC encoder performs FEC encoding on an input BBF to generateFECBLOCK procedure using outer coding (BCH) and inner coding (LDPC). Theouter coding (BCH) is optional coding method. The bit interleaver mayinterleave outputs of the data FEC encoder to achieve optimizedperformance with a combination of LDPC codes and a modulation schemewhile providing an efficiently implementable structure. A detailedoperation of the bit interleaver will be described later.

The constellation mapper may modulate each cell word from the bitinterleaver or the cell-word demultiplexer in the advanced profile usingeither QPSK, QAM-16, non-uniform QAM (NUQ-64, NUQ-256, or NUQ-1024) ornon-uniform constellation (NUC-16, NUC-64, NUC-256, or NUC-1024) mappingto give a power-normalized constellation point. This constellationmapping is applied only for DPs. It is observed that QAM-16 and NUQs aresquare shaped, while NUCs have arbitrary shapes. Both NUQs and NUCs aredefined specifically for each code rate and the particular one used issignaled by the parameter DP_MOD field in the PLS2 data. The timeinterleaver may operates at a DP level. Parameters of time interleaving(TI) may be set differently for each DP. The time interlaever accordingto an embodiment of the present invention can be positioned between aBICM chain block and a frame builder.

Here, The time interlaever according to an embodiment of the presentinvention can use both a convolutional interleaver (CI) and a blockinterleaver (BI) or selectively using either the CI or the BI accordingto a physical layer pipe (PLP) mode. A PLP according to an embodiment ofthe present invention is a physical path corresponding to the sameconcept as that of the above-described DP, and a name of the PLP may bechanged by a designer. A PLP mode according to an embodiment of thepresent invention may include a single PLP mode or a multi-PLP modeaccording to the number of PLPs processed by a broadcast signaltransmitter or a broadcast signal transmission apparatus. In the presentinvention, time interleaving in which different time interleavingschemes are applied according to PLP modes may be referred to as hybridtime interleaving.

The hybrid time interleaver may include a BI and a CI. That is, whenPLP_NUM=1, the BI is not applied (BI is turned OFF) and only the CI isapplied. When PLP_NUM>1, both the BI and the CI may be applied (BI isturned ON). A structure and an operation of the CI applied whenPLP_NUM>1 may be different from a case of PLP_NUM=1. The hybrid timedeinterleaver may perform an operation corresponding to an inverseoperation of the hybrid time interleaver described above.

The cell-word demultiplexer is used for dividing a single cell-wordstream into dual cell-word streams for MIMO processing. The MIMOencoding block may process an output of the cell-word demultiplexerusing a MIMO encoding scheme. The MIMO encoding scheme of the presentinvention may be defined as full-rate spatial multiplexing (FR-SM) toprovide capacity increase with relatively small complexity increase atthe receiver side. MIMO processing is applied at the DP level. NUQ (e1,iand e2,i) corresponding to a pair of constellation mapper outputs is fedto an input of a MIMO encoder and paired MIMO encoder output (g1,i andg2,i) is transmitted by the same carrier k and OFDM symbol I ofrespective TX antennas thereof.

The frame building block 1020 may map the data cells of the input DPsinto the OFDM symbols within a frame, and perform frequency interleavingfor frequency-domain diversity.

A frame according to an embodiment of the present invention is furtherdivided into a preamble, one or more frame signaling symbols (FSSs),normal data symbols. The preamble provides a set of basic transmissionparameters for efficient transmission and reception of a signal. And thepreamble indicates whether the emergency alert service (EAS) is providedin a current frame or not. A main purpose of the FSS is to carry PLSdata. For fast synchronization and channel estimation, and hence fastdecoding of PLS data, the FSS has a dense pilot pattern than a normaldata symbol.

The frame building block 1020 may include a delay compensation block foradjusting timing between DPs and corresponding PLS data to ensure thatthe DPs and the corresponding PLS data are co-timed at a transmitterside, a cell mapper for mapping PLS, DPs, auxiliary streams, dummycells, etc. to active carriers of the OFDM symbols in the frame and afrequency interleaver.

The frequency interleaver may randomly interleave data cells receivedfrom the cell mapper to provide frequency diversity. In addition, thefrequency interleaver may operate on data corresponding to an OFDMsymbol pair including two sequential OFDM symbols or an OFDM symbolusing a different interleaving-seed order to obtain maximum interleavinggain in a single frame.

The OFDM generation block 1030 modulates OFDM carriers by cells producedby the frame building block, inserts pilots, and produces a time domainsignal for transmission. In addition, this block subsequently insertsguard intervals, and applies peak-to-average power ratio (PAPR)reduction processing to produce a final RF signal.

The signaling generation block 1040 may create physical layer signalinginformation used for an operation of each functional block. Signalinginformation according to an embodiment of the present invention mayinclude PLS data. The PLS data includes PLS1 data and PLS2 data.

The PLS1 data is a first set of PLS data carried in an FSS symbol in aframe having a fixed size, coding and modulation, which carries basicinformation about the system in addition to the parameters needed todecode the PLS2 data. The PLS1 data provides basic transmissionparameters including parameters required to enable reception anddecoding of the PLS2 data. In addition, the PLS1 data remains constantfor the duration of a frame group. The PLS2 data is a second set of PLSdata transmitted in an FSS symbol, which carries more detailed PLS dataabout the system and the DPs. The PLS2 contains parameters that providesufficient information for the receiver to decode a desired DP. The PLS2signaling further includes two types of parameters, PLS2 static data(PLS2-STAT data) and PLS2 dynamic data (PLS2-DYN data). The PLS2 staticdata is PLS2 data that remains static for the duration of a frame groupand the PLS2 dynamic data is PLS2 data that dynamically changes frame byframe.

PLS2 data can include FIC_FLAG information. FIC (fast informationchannel) is a dedicated channel for carrying cross-layer information toenable fast service acquisition and channel scanning. FIC_FLAG is a1-bit field and indicates whether the FIC is used in a current frame. Ifthis field is set to ‘1’, the FIC is provided in the current frame. Ifthis field set to ‘0’, the FIC is not carried in the current frame.

The BICM block 1010 may include BICM block for protection of the PLSdata including a PLS FEC encoder, a bit interleaver and a constellationmapper.

The PLS FEC encoder may include a scrambler for scrambling PLS1 data andPLS2 data, a BCH encoding/zero insertion block for outer encoding on thescrambled PLS 1,2 data using a shortened BCH code for PLS protection,and insert zero bits after BCH encoding, an LDPC encoding block for LDPCencoding using an LDPC code and an LDPC parity puncturing block. The bitinterleaver may interleave each of shortened and punctured PLS1 data andPLS2 data. The constellation mapper may map the bit-ineterlaeved PLS1data and PLS2 data to constellations.

The broadcast signal reception apparatus for future broadcast servicesaccording to the embodiment of the present invention may correspond tothe broadcast signal transmission apparatus for future broadcastservices described with reference to FIG. 8.

The broadcast signal reception apparatus for future broadcast servicesaccording to the embodiment of the present invention may include asynchronization & demodulation module carrying out demodulationcorresponding to a reverse procedure of a procedure performed by thebroadcast signal transmission apparatus, a frame parsing module parsinginput signal frames and extracting data through which a service selectedby a user is transmitted, a demapping & decoding module which convertinput signals into bit domain data and then deinterleave the same asnecessary, perform demapping of mapping applied for transmissionefficiency and correct an error generated on a transmission channelthrough decoding, an output processor performing reverse procedures ofvarious compression/signal processing procedures which are applied bythe broadcast signal transmission apparatus and a signaling decodingmodule obtaining PLS information from a signal demodulated by thesynchronization & demodulation module. The frame parsing module, thedemapping & decoding module and the output processor may executefunctions thereof using data output from the signaling decoding module.

Hereinafter, time interleaver is described. According to an embodimentof the present invention, each TI group is either mapped directly to oneframe or spread over PI frames. Each TI group is also divided into morethan one TI block (N_TI), where each TI block corresponds to one usageof a time interleaver memory. The TI blocks within the TI group maycontain slightly different numbers of XFECBLOCKs. Typically, the timeinterleaver may also function as a buffer for DP data prior to a processof frame building.

The Time interleaving according to an embodiment of the presentinvention is a twisted row-column block interleaver. The twistedrow-column block interleaver according to an embodiment of the presentinvention may column-wise wite a first XFECBLOCK into a first column ofa TI memory, and a second XFECBLOCK into a next column, and so on).Then, in an interleaving array, cells are diagonal-wise readdiagonal-wise from a first row (rightwards along a row beginning with aleft-most column) to a last row, Nr cells are read out. Moreover, inorder to achieve single-memory deinterleaving at a receiver sideregardless of a number of XFECBLOCKs in a TI block the twistedrow-column block interleaver may insert the virtual XFECBLOCKs into theTI memory. The virtual XFECBLOCKs must be inserted infront of otherFECBLOCKS to achieve single-memory deinterleaving at a receiver side.

FIG. 9 illustrates a write operation of a time interleaver according toan embodiment of the present invention.

A left block in the figure illustrates a TI memory address array, andright blocks in the figure illustrate a write operation when two virtualFEC blocks and one virtual FEC block are inserted into heads of twocontiguous TI groups, respectively.

The frequency interleaver according to the present embodiment mayinclude an interleaving address generator for generating an interleavingaddress for applying corresponding data to a symbol pair.

FIG. 10 illustrates an interlaving address generator including a mainpseudo-random binary sequence (PRBS) generator and a sub-PRBS generatoraccording to each FFT mode which are included in a frequencyinterleavaer according to an embodiment of the present invention.

(a) shows the block diagrams of the interleaving-address generator for8K FFT mode, (b) shows the block diagrams of the interleaving-addressgenerator for 16K FFT mode and (c) shows the block diagrams of theinterleaving-address generator for 32K FFT mode.

The interleaving process for the OFDM symbol pair is described asfollows, exploiting a single interleaving-sequence. First, availabledata cells (the output cells from the Cell Mapper) to be interleaved inone OFDM symbol O_(m,I) is defined as O_(m,I)=[x_(m,I,o), . . . ,x_(m,I,p), . . . , x_(m,I,Ndata−1)] for I=0, . . . , N_(sym)−1, wherex_(m,I,p) is the p^(th) cell of the I^(th) OFDM symbol in the m^(th)frame and N_(data) is the number of data cells: N_(data)=C_(FSS) for theframe signaling symbol(s), N_(data)=C_(data) for the normal data, andN_(data)=C_(FES) for the frame edge symbol. In addition, the interleaveddata cells are defined as P_(m,I)=[v_(m,I,o), . . . , v_(m,I,Ndata−1)]for I=0, . . . , N_(sym)−1.

For the OFDM symbol pair, the interleaved OFDM symbol pair is given by

v_(m,I,Hi(p))=x_(m,I,p), p=0, . . . ,N_(data)−1, for the first OFDMsymbol of each pair

v_(m,I,p)=x_(m,I,Hi(p)), p=0, . . . ,N_(data)−1 for the second OFDMsymbol of each pair,

where H_(l)(p) is the interleaving address generated based on a PRBSgenerator and a cyclic shift value (symbol offset) of a sub-PRBSgenerator.

## Hereinafter, a method for transmitting a broadcast signal accordingto another embodiment of the present invention is described.

In FIG. 1, the Service List Table may be transmitted with being includedin Low Level Signaling information. The LLS information may betransmitted in a UDP/IP layer, and may also be referred to as an LLStable. Since the LLS information is not encoded in a delivery layer butis transmitted in the IP packet format, the LLS information may beprocessed more quickly in a receiver, and accordingly, the delay causedto provide a service when the receiver is turned on.

The broadcast service may be delivered by using three functional layers.The three layers include a physical layer, a delivery layer and aservice management layer. The physical layer may provide a mechanism inwhich signaling, service announcement and IP steams are transported tothe physical layer. The delivery layer may provide an object or objectflow transport functionality. The delivery layer may transport an objectby using Real-Time Object Delivery over Unidirection Transport (ROUTE)protocol. The ROUTE protocol that operates in UDP/IP multicast over thebroadcast physical layer and the HTTP protocol that operates in TCP/IPunicast over the broadcast physical layer may be used in the deliverylayer. The service management layer enables services of arbitrary typessuch as linear TV and HTML5 application service to be transported in thedelivery layer and the physical layer.

In this specification, a Fast Information Table (FIT) may also bereferred to as a Service List Table (SLT).

FIG. 11 illustrates a service delivery and signaling structure accordingto an embodiment of the present invention.

The service signaling may provide service discovery and descriptioninformation, and may include two functional components—bootstrapsignaling through SLT and SLS. The SLT and the SLS indicate theinformation required to discover and obtain a user service.

The SLT enables to obtain the basic service information fast. The SLSprovides information required for a receiver to discover and access abroadcast service (e.g., ATSC 3.0) and the contents components. Therelationship between the SLT and SLS signaling (for ROUTE/DASH services)and an MMT signaling will be described below. However, the MMT signalingmay also be referred to as the SLS.

For the broadcast delivery of the ROUTE/DASH services, the SLS may betransmitted to ROUTE/UDP/IP from one of the LCT transport sessionsincluding a ROUTE session. The SLS may be transmitted to a propercarousel rate that supports fast channel joint and switching. In thebroadband delivery, the SLS may be carried on HTTP(S)/TCP/IP.

As shown in FIG. 11, a service in the broadcast system of the presentinvention may be delivered though ROUTE protocol and MMT protocol, andthe SLS for the service delivered through each protocol may also bedelivered through each protocol.

FIG. 12 illustrates logical entity and relationship of a servicemanagement, delivery and physical layers according to an embodiment ofthe present invention.

The ROUTE/LCT session and/or the MMTP sessions that deliver the contentcomponent of a broadcast service may be composed as below. With respectto a broadcast delivery of a linear service without application-basedenhancement, the service content component may be delivered by at leastone of at least one ROUTE/LCT session or at least one MMTP session. Withrespect to a broadcast delivery of a linear service withapplication-based enhancement, the service content component may bedelivered by at least one of at least one ROUTE/LCT session or zero ormore MMTP sessions. For streaming of the media components in the sameservice, it may be prohibited that the MMTP and the ROUTE are usedtogether. With respect to a broadcast delivery of the application-basedservice, the service content components may be delivered by at least oneROUTE/LCT session.

Each ROUTE session includes at least one LCT session that carries thecontent component that constructs a broadcast service. With respect to astreaming service delivery, the LCT session may deliver an individualcomponent of a user service such as audio, video or caption stream. Thestreaming media may be formatted per MPEG-DASH as a DASH segment. EachMMTP session may include at least one MMTP packet flow that delivers acontent component or an MMT signaling. The MMTP packet flow may delivera component formatted per MMT or an MMT signaling message, as MPUs. Withrespect to the NRT user service or system metadata, the LCT session maydeliver a file-based content item. The content file may includecontinuous (time-based) or discrete (non-time-based) media component ofthe NRT service or metadata such as a service signaling or ESG fragment.

A broadcast steam is an extraction of an RF channel, and may be definedas a carrier frequency centered in a specific bandwidth. The PLPcorresponds to a portion of an RF channel. Each PLP has a specificmodulation and coding parameter. The PLP may be identified by a uniquePLP identifier (PLPID) in the broadcast stream to which the PLP isbelonged.

Each service may be distinguished two types of forms of the serviceidentifiers. One is a compact form used in the FIT, which is unique onlyin a broadcast area and another is a globally unique form used in theSLS and the ESG. The ROUTE session may be distinguished by a source IPaddress, a destination IP address and a destination port number. The LCTsession may be distinguished by a unique Transport Session Identifier(TSI) in a ROUTE session. The common properties in the LCT sessions andspecific properties with respect to each LCT session may be provided bythe ROUTE signaling structure which is designated by Service-basedTransport Session Instance Description (S-TSID), and the S-TSID is apart of the service level signaling. Each of the LCT sessions may bedelivered by a single PLP. The different LCT sessions in the ROUTEsession may be included in different PLPs. The properties described inthe S-TSID may include TSI value and PLPID for each LCT session,descriptor for deliver object/files and application layer FECparameters.

The MMTP session may be distinguished by a source IP address, adestination IP address and a destination port number. The MMTP packetflow may be distinguished by a unique packet_id in a scoop of a parentMMTP session. The common properties with respect to each MMTP packetflow and specific property with respect to the MMTP packet flow may bedescribed in the SLT. Each MMTP packet flow may be carried on a singlePLP. Different MMTP packet flows of an MMTP session may be included ornot included in different PLPs. The property described in an MMTsignaling message may include PLP ID information and packet IDinformation for each MMTP packet flow.

FIG. 13 illustrates a method for using a service signaling forbootstrapping and service discovery according to an embodiment of thepresent invention.

As an embodiment, signaling information may be carried as a payload ofan IP packet that has a public/known address, and the signalinginformation may be referred to as a Link Layer Signaling (LLS) or aService List Table (SLT). The point on which a receiver starts tooperate when receiving a broadcast signal may be the LLS. The LLS may beused to build a list of services received by a receiver such as achannel name and a channel number. In addition, the LLS may also providebootstrap information that enables a receiver to discover the LSLinformation for each service. The bootstrap information may include adestination IP address, a destination port and a TSI of the LCT sessionthat delivers the SLS. With respect to MMT/MPD delivery service, thebootstrap information may include a destination IP address, adestination port and a packet IP of a service layer signaling MMTPchannel.

With respect to ROUTE/DASH, the SLS for each service may describeattributes of services such as the capability of a receiver required toprovide a meaningful presentation of a service, a location on which aservice is available to be obtained, and a list of components. In theROUTE/DASH system, the SLS may include User Service Bundle Description(USBD), S-TSID and DASH Media Presentation Description (MPD). Thedetailed description of USBD will be described below.

Since a separate service signaling is used with respect to each service,a receiver obtains the SLS only for a wanted service without the need toparse all SLSs within a broadcast stream, thereby decreasing unnecessaryprocessing of the receiver. For the optional broadband delivery of aservice signaling, the SLT may also include a HTTP URL in which aservice signaling file may be obtained. When an update occurs in an SLSsignaling, an event may be detected by a version field of the SLT. Inaddition, the updated signaling may be obtained by broadcast or inbroadband.

As shown in FIG. 13, the LLS is used for obtaining the SLS, and the SLSmay be used for obtaining a service component which is delivered withROUTE/LCT transport session. A receiver may obtain the SLT. Each serviceidentified by a service ID may provide SLS bootstrapping information.The SLS bootstrapping information may include a PLPID, a source IPaddress (sIP1), a destination IP address (sIP1), a destination portnumber (dPort1) and a TSI (tsi-SLS).

A receiver may obtain an SLS fragment which is delivered with IP/UDP/LCTsession and the PLP. These fragments may include a USBD/USD fragment, anS-TSID fragment and an MPD fragment. These fragments may be associatedwith a single service. The USBD/USD fragment may include a URI thatdescribes a service level attribute and refers to the S-TSID fragmentand a URI that refers the MPD fragment.

The S-TSID fragment may be provide the component acquisition informationin relation to a service and a mapping between DASH Representationdiscovered in the MPD and the TSI corresponding to a component of aservice. The S-TSID may provide component acquisition information of aTSI form, a DASH Representation identifier and a PLP ID that deliversDASH segment in relation to the DASH Representation. By using the PLPIDand the TSI values, a receiver may collect audio/video components, andmay buffer DASH media segment by applying an appropriate decodingprocessing. Service #2 distinguished by a service ID (service_id,0x1002) may provide the MMTP session description information thatincludes an MMT signaling message—PLPID(#2), a source IP address (sIP2),a destination IP address (dIP2), a destination port number (dPort2) anda packet ID (packet_id-2). A receiver may obtain an MMT signalingmessage carried through the IP/UDP/MMTP session and/or the PLP. Thesemessages may include MPT table(s) associated with a service. By usingthe MMTP signaling message, a receiver may collect audio/video componentfrom a service and start an MPT processing.

The hierarchical signaling architecture of a broadcast system will bedescribed in more detail below.

A service signaling provides the bootstrap and discovery informationwith respect to a service which is currently “on the air”. TheElectronic Service Guide (ESG) provides the contents accompanyingdetailed information including a device performance, a content ratingand a presentation schedule and a user service announcement announcingan available broadcast service and a content list. The ESG informationmay be provided such that a user may select a service or content. TheESG information may be required for a receiver to determine whether itis the content or service to be watched by a user. The linkage between aservice of the ESG and a service of the SLS may be described by aservice identifier.

Generally, the low level signaling (LLS) may also be operated under theIP level. In the reception side, the LLS may also be obtained fasterthan the IP level signaling. The LLS may be obtained before the sessionestablishment. The LLS may be used for performing fast channel scan andfast service acquisition efficiently. The LLS may include the bindinginformation between the service signaling and the PLP. In addition, theLLS may include the signaling information in relation to the EmergencyAlert (EA).

The SLS may also include the USBD and the S-TSID metadata fragment. TheUSBD may include service identification and device performanceinformation. In addition, the USBD may include different SLS fragmentrequired to access to a service and a media component and metadatarequired for a receiver to determine a transport mode (broadcast and/orbroadband). The S-TSID fragment may provide the transport sessiondescription with respect to an MMTP session or a ROUTE/LCT sessionthrough which a media content component is delivered, and may providethe description with respect to deliver objects delivered in an LCTsession.

The streaming content signaling component of the SLS may also correspondto a Media Presentation Description (MPD). The MPD is a streamingcontent, and may be associated with the linear services for a deliveryof DASH segments. The MPD may be used for supporting application-basedservice, and may be in relation to the DASH-formatted contentcomponents, and the MPD may be used for controlling a play out of thecontents. The MPD may provide the resource identifier for an individualmedia component of linear/streaming service with a segment URL form, andmay provide a context of the resources identified in the mediapresentation. The application-based enhancement signaling may be appliedto a delivery of the application-based enhancement component such as anapplication logic file, an NRT media file, an on-demand contentcomponent or a notification stream.

FIG. 14 illustrates SLT information according to an embodiment of thepresent invention.

The SLT supports a fast channel scan and a service acquisition. The SLTenables a viewer to present a meaningful service list, and includesinformation supporting a service selection through channel up/downzapping. In addition, the SLT includes bootstrap information that maylocate a position of a service layer signaling throughbroadcast/broadband depending on whether a signaling is available. Thebit stream syntax of the SLT is as shown in FIG. 14. The description foreach of the fields is as below.

table_id: An unsigned integer of 8 bits, and may be configured that atable is to represent an SLT section.

SLT_section_version: A field of 4 bits, and may represent a versionnumber of an SLT section. The value of this field may be increased by 1when the included information is changed. When the field value reachesto ‘1111’ which is the maximum value, the value may return to 0 again.

SLT_section_length: This 12 bits field may represent a byte number ofinstance of an SLT section. The represented length may be started rightafter SLT_section_length field.

SLT_protocol_version: An unsigned integer of 8 bits, and represents theversion of the SLT structure. Upper 4 bits of the field may representthe major version, and lower 4 bits may represent the minor version. Asan embodiment, the value of this field may be set to 0x10 so as torepresent version 1.0.

broadcast_stream_id: An unsigned integer of 16 bits, and may identifythe entire broadcast stream. Uniqueness of the field value may be therange of a geographic area (e.g., North America).

SLT_section_number: An unsigned integer of 4 bits, and may represent thenumber of section starting from zero. The SLT may include multiple SLTsections.

last_SLT_section_number: This field may represent the section that hasthe highest value of the SLT_section_number of the SLT which is a partof the current SLT section. For example, in the case that thelast_SLT_section_number field has ‘0010’ value, may which representthere are total three sections labeled with ‘0000’, ‘0001’ and ‘0010’.

num_services: An unsigned integer of 8 bits, and may represent thenumber of services described in the service_list_table_section( ).

service_id: An unsigned integer of 16 bits that identifies the servicein a scope of a broadcast area.

SLT_service_seq_number: This field represents a sequence number of theservice information that has a service ID such as the service_id fieldin the repetition of “for” loop. The SLT_service_seq_number may bestarted from zero for each service and may be increased by 1 when theSLT service information for the service identified by the service_id ischanged. In the case that the SLT service information for a specificservice is not changed in comparison with the past service informationthat has a specific value of the SLT_service_seq_number, theSLT_service_seq_number field value is not increased. TheSLT_service_seq_number field value returns to zero when it reaches themaximum value.

protected: A flag of 1 bit, and when it is set, this represents that atleast one component required for a meaningful presentation may beprotected. When it is set to ‘0’, this flag may represent that thecomponent required for a meaningful presentation of a service is notprotected.

major_channel_number: An unsigned integer of 10 bits in the range of 1to 999, and represents a “major” channel number of the service definedin the repetition of “for” loop. Each service may be in relation to amajor channel number and a minor channel number. The major channelnumber may function as a reference number of a user for a virtualchannel like the minor channel number. The major channel number is setsuch that a pair of the major channel number/the minor channel number isnot overlapped.

minor_channel_number: An unsigned integer of 10 bits in the range of 1to 999, and represents a “minor” or “sub” channel number of the servicedefined in the repetition of “for” loop. This field provides a channelnumber of two parts of a service together with the major channel number,and the minor channel number represents the second or the right number.

service_category: An unsigned integer field of 4 bits, and may representa service category as represented in Table 1 below.

TABLE 1 Service category Meaning 0x00 not specified 0x01 Linear A/Vservice 0x02 Linear audio only service 0x03 App-based service 0x04~0x0fReserved for future use

short_service_name_length: An unsigned integer field of 4 bits, andrepresents the length of the subsequent short_service_name( ) field. Inthe case that there is no short name provided for this service, thisfield may be set to zero.

short_service_name( ): This field represents a short name of a service,in the case that this field is present. Each character of the term maybe encoded per UTF-8.

broadcast_signaling_present: A Boolean flag of 1 bit, and in the casethat it is set to ‘1’, this represents that there exist the fieldsstarted from SLS_PLP_ID and ended in the fields in relation tonum_ext_length_bits in Table of FIG. 14.

SLS_source_IP_address_present: A Boolean flag of 1 bit, and in the casethat it is set to ‘1’, this represents that the SLS_source_IP_addressfield is present. In the case that it is set to ‘0’, this representsthat the SLS_source_IP_address field is not present.

broadband_access_required: A Boolean flag of 1 bit, and in the case thatit is set to ‘1’, this may represent that a broadband access is requiredin order for a receiver to provide a meaningful presentation of theservice identified by a service ID. In the case that it is set to ‘0’,this may represent that a broadband access is not required in order fora receiver to provide a meaningful presentation of the serviceidentified by a service ID.

SLS_protocol_type: An unsigned integer field of 4 bits, and represents aprotocol type of an SLS channel on UDP/IP with respect to the servicedescribed in “for” loop. This bit may be coded as represented in Table2. A receiver parses a part of data field, and may ignore the service inthe case that the SLS_protocol_type is unknown or unsupported. Table 2represents an embodiment of code values of the SLS protocol typeinformation.

TABLE 2 SLS protocol type Meaning 0x00 Reserved 0x01 ROUTE 0x02 MMTP0x03 Reserved 0x04~0x0F Reserved

SLS_PLP_ID: An unsigned integer field of 4 bits, and represents an ID ofthe PLP that includes SLS data for this service. The PLP may be morerobust than other PLP used by the service.

SLS_destination_IP_address: This field represents IPv4 destination IPaddress of 32 bits of an SLS channel for the service.

SLS_destination_UDP_port: This field represents a destination UDP portnumber of an SLS channel for the service.

SLS_source_IP_address: This field represents a source IPv4 address inrelation to an SLS for the service, in the case that it is present.

SLS_protocol_version: An unsigned integer field of 8 bits, and mayrepresent a version of the protocol identified in the SLS protocol typefield that may be used for providing the SLS for the service. Themeaning of the SLS protocol version information may depend on theprotocol (e.g., a value of the SLS protocol type information) which isused. In the case that the SLS_protocol_type value is 0x01, that is, inthe case of representing the ROUTE protocol, the MSB 4 bits of theSLS_protocol_version field represents the major protocol version of theROUTE protocol, and the LSB 4 bits may represent the minor protocolversion of the ROUTE protocol. As an embodiment, with respect to theROUTE protocol, the major version number may be 0x1, and the minorversion number may be 0x0. In the case that the SLS_protocol_type valueis 0x02, that is, in the case of representing the MMT protocol, the MSB4 bits of the SLS_protocol_version field represents the major protocolversion of the MMT protocol, and the LSB 4 bits may represent the minorprotocol version of the MMT protocol. As an embodiment, with respect tothe MMT protocol, the major version number may be 0x1, and the minorversion number may be 0x0.

Receivers may not provide a user service which is labeled with a valueof the major protocol version higher than that of the receivers support.In addition, a receiver may not provide a service on the bases of theminor protocol version to a user. A receiver may determine whether atransmitted data includes a data element defined in the latest versionof the standard by using the minor protocol version.

num_service_level_descriptors: This field represents the number of zeroor more descriptors that provide additional information for the service.The unsigned integer field of 4 bits may represent the number of servicelevel descriptors for the service. In the case that the field value iszero, this represents there is no descriptor.

service_level_descriptor( ): The format of each descriptor may be a typefield of 8 bits, and may be connected to a length field of 8 bits. Thelength field may represent the byte number of a length field subsequentdata.

num_SLT_level_descriptors: This field represents the number of zero ormore descriptors that provides additional information for the SLT. Theunsigned integer field of 4 bits may represent the number of SLT leveldescriptors included in the service_list_table_section( ). In the casethat the field value is zero, this represents there is no descriptor.

SLT_level_descriptor( ): The format of each descriptor may be a typefield of 8 bits, and may be connected to a length field of 8 bits. Thelength field may represent the byte number of a length field subsequentdata.

Zero or one or more descriptors may provide additional information for aset of services delivered by a specific service or the SLT instance. TheSLT descriptor includes a descriptor tag, and the descriptor tag mayrepresent at least one of a descriptor which is defined, a reference ora position in the SLT. A specific descriptor may be needed to exist in aspecific situation. For example, the descriptors such asinet_signaling_location_descriptor( ), service_language_descriptor( )and capabilities_descriptor( ) may be included in at least one level ofa service level or an SLT level.

The SLT described above may be signaled in XML format.

FIG. 15 illustrates an XML format of the SLT according to an embodimentof the present invention.

FIG. 16 illustrates an XML format of InetSigLocation informationaccording to an embodiment of the present invention.

For FIG. 15 and FIG. 16, the description in relation to FIG. 3 and FIG.14 is not overlapped.

FIG. 17 illustrates a service layer signaling data model according to anembodiment of the present invention.

The SLS may provide detailed technical information for a broadcastreceiver to discover and access a broadcast service and the contentcomponent of the broadcast service. The SLS may include a set ofXML-encoded metadata fragments delivered to a dedicated LCT session. TheLCT session that delivers the SLS may be obtained from the bootstrapinformation included in FIT. The SLS is defined in a service level, anddescribes the property of service and the access information. The SLSmay include a list of content components, the information on how toobtain it and the information such as the receiver performance requiredto generate a meaningful presentation of a service. In the ROUTE/DASHsystem for the linear service delivery, the SLS may include USBD, S-TSIDand DASH MPD. The SLS fragments may be delivered through an LCTtransport session that has a public TSI value.

FIG. 18 illustrates a USBD according to an embodiment of the presentinvention.

The USBD of FIG. 18 is another embodiment of the USBD of FIG. 4, and thecommon description may be omitted. The USBD is the most significant orentry point SLS fragment.

The description for elements (attributes) included in the USBD of FIG.18 is as below.

bundleDescription: A loot element of the USBD

userServiceDescription: A single instance of ATSC 3.0 service

@serviceId: A globally unique identifier of ATSC 3.0 service

@atsc:serviceId: A reference to the corresponding service entry in anLLT (FIT). The value of a service identifier assigned in the entry isthe same as the value of the attribute.

@atsc:fullMPDUri: A reference to an MPU fragment that includes adescription for a content component of ATSC 3.0 service which isdelivered by broadcast or (optionally) broadband.

@atsc:sTSIDUri: A reference to an S-TSID fragment that provides anaccess to a related parameter with respect to a transport session thatcarries a content of ATSC 3.0 service.

name: A term of ATSC 3.0 service given by language (lang) attribute.

lang: A language of ATSC 3.0 service term. The language may be specifiedaccording to XML data type (XML Schema Part 2 [7]).

serviceLanguage: An available language of ATSC 3.0 service. The languagemay be specified according to XML data type (XML Schema Part 2 [7]).

atsc:capabilityCode: This field represents a performance or aperformance group defined in ATSC 3.0 service announcement and theindividualization standard, and represents a performance of a receiverthat is able to generate a meaningful representation of thecorresponding ATSC service content. The format of the element may be thesame as the atsc:capabilities element described under the ATSC 3.0service announcement and the content fragment of the individualizationdocument.

deliveryMethod: Container of transport related information pertaining tothe contents of the service over broadcast and (optionally) broadbandmodes of access.

atsc:broadcastAppService: DASH Representation delivered over broadcast,in multiplexed or non-multiplexed form, containing the correspondingmedia component(s) belonging to the ATSC 3.0 Service, across all Periodsof the affiliated Media Presentation (MP).

basePattern: A character pattern for use by the ATSC receiver to matchagainst any portion of the Segment URL used by the DASH client torequest Media Segments of a parent Representation under its containingPeriod. A match implies that the corresponding requested Media Segmentis carried over broadcast transport.

atsc:unicastAppService: DASH Representation delivered over broadband, inmultiplexed or non-multiplexed form, containing the constituent mediacontent component(s) belonging to the ATSC 3.0 Service, across allPeriods of the affiliated Media Presentation.

basePattern: A character pattern for use by the ATSC receiver to matchagainst any portion of the Segment URL used by the DASH client torequest Media Segments of a parent Representation under its containingPeriod. A match implies that the corresponding requested Media Segmentis carried over broadcast transport.

FIG. 19 illustrates an S-TSID according to an embodiment of the presentinvention.

The S-TSID of FIG. 19 is another embodiment of the S-TSID of FIG. 6, andthe common description may be omitted. The S-TSID includes overalltransport session description with respect to a ROUTE session, an LCTsession or an MMTP session, through which the media content componentsin which a service is delivered are delivered. The S-TSID may include adelivery object delivered in the LCT session of a service or metadatafor an object flow. The S-TSID may also include additional informationwith respect to a content component and a payload format delivered inthe LCT session. The S-TSID is signaling data in a unit of service.

The description for elements (attributes) included in the S-TSID of FIG.19 is as below.

S-TSID: Service transport session instance description

RS: ROUTE session

@bsid: An identifier of a broadcast stream in a content component onwhich broadAppService is carried. In the case that the attribute is notpresent, The PLP that carries an SLS fragment for ATSC 3.0 service isincluded in a default broadcast stream. The ID value may be the same asthe value of a broadcast stream ID in the FIT.

@sIpAddr: A source IP address (default: the source address of thecurrent ROUTE session, and M for non-primary session.)

@dIpAddr: A destination IP address (default: the destination address ofthe current ROUTE session, and M for non-primary session.)

@dport: A destination port (default: the destination port of the currentROUTE session, and M for non-primary session.)

@PLPID: PIP ID for a ROUTE session (default: the current PLP).

LS: LCT session

@tsi: TSI value

@PLPID: PIP ID (overrides default ROUTE session value)

@bw: Maximum bandwidth

@startTime: Start time

@endTime: End time

SrcFlow: Source flow defined in ATSC 3.0 Delivery & Synchronization spec[3]

RprFlow: Repair flow defined in ATSC 3.0 Delivery & Synchronization spec[3]

Each instance of the S-TSID may be referred in the USBD fragment.

The MPD is an SLS metadata fragment including a formalized descriptionof the DASH media presentation, which corresponds to a linear service inthe duration defined by a broadcaster. The content of the MPD provides acontext for resources identified in the media presentation and aresource identifier for the segments. In the context of a broadcastservice, at least one representation conveyed by the MPD may betransmitted in broadcast manner. As an embodiment, the representationmay be carried through at least one representation broadcast included inthe MPD. The MPD may also describe an additional representation.

FIG. 20 illustrates a hierarchical signaling structure according to anembodiment of the present invention.

In FIG. 20, the SLT is transmitted with being included in the LLS, andthe LLS is delivered with UDP/IP encapsulated IP packet. FIG. 20 showsan embodiment in which two S-TSIDs are delivered. A single S-TSIDprovides the access information for an LCT session belonged to ROUTEsession #1. In addition, the second S-TSID provides the accessinformation for an LCT session belonged to ROUTE session #N. As anembodiment, the UDP/IP encapsulated LLS may be link layer packetized andmay be transmitted to PLP#0.

The PLP that carries the SLT may deliver a service component as well asthe SLT. In the embodiment, since the SLS may be delivered to the PLPthat delivers the SLT, the PLP ID information in the SLT may be omitted.

In a broadcast stream, multiple SLTs may be included.

## As described above, the LLS information may include the SLTinformation, and also include the information related to Emergency Alert(EA). Hereinafter, the EA related information carried by the LLSinformation is described. The EA related information may also bereferred to as EA information.

The EA information is needed to be broadcasted rapidly and provided to auser in an emergency situation. Accordingly, the EA information may betransmitted through different path from the ordinary service data. Inthe broadcast system described above, the EA information may betransmitted by using a dedicated channel for the EA information or aspecific PLP. However, in such a case, since a data/signal is needed tobe processed or inserted in a physical layer, the system operation forthe EA information may become difficult. Accordingly, a method isdescribed for transmitting the EA information by using UDP/IP packet.

The EA information may be transmitted with IP packet instead of beingtransmitted with a link layer signaling or a physical layerchannel/data. Particularly, in the IP-based broadcast system describedabove, the IP-based EP information may generate an effect that enablesthe system management to be easy. For this, additional signalinginformation on which IP packet the EA related information is deliveredmay be constructed. As an embodiment, by using a header part of apacket, it may be represented that the EA information is included ornot. In this specification, the packet or the table included in the EArelated information may be referred to an EA packet. The LLS informationmay be transmitted in an IP packet and the LLS information may includethe EA information. Accordingly, the EA packet in which the EA relatedinformation is included may be included in the LLS information.

FIG. 21 illustrates a method for transmitting EA information usingUDP/IP according to an embodiment of the present invention.

A broadcast transmitter may collect a CAP message and the related dataso as to transmit the EA information through an IP (step, S21010). TheCAP message may also be referred to as an EA message. The EA relateddata may include an EA table or a packet. The Emergency Alert Table(EAT) may also be referred to the EA information or the EA message.However, the EA message may mean an EA message that should be deliveredto a user, and in this case, the signaling information required todeliver the EA message may be referred to the EA information or the EAT.

The broadcast transmitter may construct the EA related information/datain an IP packet format by UDP/IP encapsulating it (step, S21020). It isas described above that such an IP packet may be the LLS information. Ina payload of an IP packet, a table in the Emergency Alert Table (EAT)form may also be included. Otherwise, an IP packet may include the EArelated information/data as a payload. As an embodiment, afield/information representing that the data constructed in the payloadwhen encapsulating is the EA information may be added in a packetheader. Alternatively, in order to represent that it is the EAinformation, an IP address and a UDP port number may become known inadvance or a dedicated value known by a transmitter or a receiver witheach other may be used. As a dedicated value, the preconfigured IPaddress and UDP port number of the LLS information may be used.

The broadcast transmitter may perform a PHY layer processing of an IPpacket that includes the EA related information (step, S21030). The IPpacket including the EA information may be transmitted to a specificbase PLP or a normal PLP. In the case of using the base PLP, thereceiver may decode the corresponding PLP without separate signalinginformation.

The broadcast transmitter may encode the broadcast data like A/Vcontents based on a delivery protocol (step, S21040). As describedabove, the deliver protocol may be the ROUTE protocol or the MMTprotocol. In addition, the broadcast transmitter may construct thebroadcast data in an IP packet format by UDP/IP encapsulating it (step,S21050).

The broadcast receiver may perform a PHY layer processing of a receivingsignal, and may IP/UDP decoding/decapsulating the IP packets included inthe PLP (step, S21060). The broadcast receiver may decode the IP packet,and may identify whether the corresponding packet is an EA packet byidentifying the IP address and the port number from a header of the IPpacket. Alternatively, the broadcast receiver may identify the LLSinformation as the IP address and the port number, and may identify theEA related information included in the LLS information.

The broadcast receiver may extract the EA message such as a CAP messageby using a header of the EP packet and the payload information, and maydeliver it to a CAP parser or a message parser (step, S21070). Thebroadcast receiver may parse the EA related information by using the CAPparser or the message parser (step, S21080).

The broadcast receiver may receive a service data by decoding thecorresponding PLP in the case that the EA related information isincluded in the payload of the EA packet. In the case that the broadcastreceiver transmits the EA related service through the PLP which iscurrently receiving, the broadcast receiver may continuously receive thecorresponding PLP. In the case that the information in relation to anNRT service data is included in the payload of the EA packet or the CAPmessage, the broadcast receiver may receive the corresponding data. Ifit is required, the broadcast receiver may also receive the EA relatedNRT service data in the broadband. In the case that the overlappedinformation is in the payload of the EA packet or the CAP message, thebroadcast transmitter may adjust the position of the correspondinginformation properly.

FIG. 22 illustrates a method for transmitting EA information usingUDP/IP according to an embodiment of the present invention.

FIG. 22 corresponds to the case of transmitting the EA relatedinformation using a normal PLP, and the description as the sameoperation of FIG. 21 is not repeated.

In the case of using the normal PLP, it may be signaled the PLP thatcarries the EA information. That is, in order for a receiver to processthe EA information quickly, it may be signaled the PLP that carries theEA information. In order to be distinguished in a physical layer, thephysical layer signaling information may include the informationrepresenting whether the PLP included in a signal frame includes the EAinformation. In other words, since the EA information is included in theLLS information, the physical layer signaling information maysignal/indicate whether the PLP include the LLS information.

In the case that the EA information is transmitted in the same PLP asthe AV data, the broadcast transmitter may construct an IP address/portnumber of a service packet differently from an IP address/port number ofthe EA packet and transmit it. As an embodiment, the broadcasttransmitter may use a dedicated IP address and port number for the IPpacket including the EA information, and may use the IP address and theport number designated by a service signaling for the service data.

The broadcast receiver may perform a physical layer processing of thePLP. In addition, the broadcast receiver may identify the EA packet andthe service data packet using the IP address/the port number of the IPpackets. The description for the identified EA packet and the servicedata packet is as described in FIG. 21.

The broadcast receiver may receive or process the EA related informationtransmitted through the dedicated IP address and the port number, first.The broadcast receiver may process the EA related signaling and the EAmessage, and may receive the EA related audio/video data using thereceived EA signaling. That is, the broadcast receiver may identify theIP address and the port number for receiving the related audio/videodata using the EA signaling, and may provide a service of A/V contentsthrough receiving the corresponding packet stream. In the case that thecorresponding service and the data are delivered through broadband, therelated reception information (URI) may be signaled.

Hereinafter, the transmitted EA information is described.

FIG. 23 illustrates an EA message according to an embodiment of thepresent invention.

A broadcast system may construct EA information using a Common AlertProtocol (CAP) message as an EA syntax that a local broadcaster maytransmit. As an embodiment, FIG. 23 shows an EA message using EAinformation required to construct EAS framework among the fields of theCAP message. However, the EA message constructed based on the CAPmessage may also be referred to as the CAP message.

The description of the fields included in the EA message of FIG. 23 isas below. The EA message includes a required field defined in the CAPand fields for transmitting a universal alert and an advanced alertrequired in the EAS framework.

The structure of binary syntax proposed in the present invention may beconstructed with XML format.

message_identifier_str_length: A 8 bit unsigned integer value, andrepresent an identifier string of the corresponding EA message.

message_identifier_str( ): This field represents an identifier string ofthe EA message as much as a length of message_identifier_str_length.

sender_str_length: A 8 bit unsigned integer value, and means a length ofstring that means sender.

sender_str( ): A string that means a sender as much as a length ofsender_str_length.

sent_str_length: A 8 bit unsigned interger value, and means a length ofstring that means the sent information.

sent_str( ): A string that means a sender as much as a length ofsent_str_length.

status: A 4 bit unsigned integer value for representing a status of amessage, and the definition of the value follows the definition of theCAP.

msgType: A 4 bit unsigned integer value for representing a message Type,the definition of the value follows the definition of the CAP.

scope: A 4 bit unsigned integer value for representing a Scope of amessage transmission/reception, and the definition of the value followsthe definition of the CAP.

num_info: In order to represent a message constructed with one or morelanguages, an alert may have one or more types of information.

category: This field means a category of the information that constructa message. The definition of the value follows the definition of theCAP.

lang_str_length: A value that represents a length of lang_str string.

lang_str: A string that represents the language of the correspondinginfo.

event_str_length: A value that represents a length of event_str( ).

event_str( ): A string describing an event, and the related definitionfollows the definition of the CAP.

urgency: A 4 bit unsigned integer value that represents an urgency, andthe related definition follows the definition of the CAP.

severity: A 4 bit unsigned integer value that represents a severity, andthe related definition follows the definition of the CAP.

certainty: A 4 bit unsigned integer value that represents a certainty,and the related definition follows the definition of the CAP.

num_resources: A 8 bit unsigned integer, and means the number ofresources in relation to the corresponding info.

resource_desc_str_length: A string length of resource_desc_str.

resource_desc_str: A field that provides a description for a resource.

mimeType_str_length: A string length of mimeType that describes amimeType.

mimeType_str: This field represents a mimeType of a resource.

resource_location( ): This field means a position to which a resource istransmitted. The detailed syntax is defined as invention 8 below.

FIG. 24 illustrates a resource location transmitted to support theenhanced alert according to an embodiment of the present invention.

A location of a resource transmitted to support the enhanced alert mayhave the path as shown in FIG. 24. Particularly, FIG. 24 shows aresource location or a transmission path for transmitting rich mediacontent. The enhanced alert may correspond to the rich media content.

(1) As an embodiment, the rich media content may be transmitted througha protocol based on a transmission session. As an embodiment, atransmission protocol such as FLUTE, ROUTE and MMT may be used.

(2) As an embodiment, the rich media content may be transmitted withbeing included in the PLP as an IP/UDP packet.

(3) As an embodiment, in the case that the rich media contenttransmitted through a separate UDP/IP session, the rich media contentmay be transmitted through broadband.

(4) As an embodiment, the rich media content may be transmitted withbeing included in the EAT which is transmitted through an EA channel.

FIG. 25 illustrates a syntax representing a location of a resource foran enhanced alert transmission according to an embodiment of the presentinvention.

The structure of binary syntax proposed in the present invention may beconstructed with XML format. The description of the fields included inthe resource location syntax of FIG. 25 is as below.

location_type: This field means a type of a resource location.

0x01: A resource is transmitted through a single LCT session like FLUTE.

0x02: A resource is transmitted through a UDP/IP session.

0x03: A URL which is downloadable through broadband is specified.

0x04: This means the case that a resource itself is transmitted withbeing embedded.

Hereinafter, a method for signaling a resource location according to alocation type is described based on the resource location information ofFIG. 25.

(1) In the case that a resource location type is 0x01, a resourcelocation may be signaled by the following information.

PLP_ID: An identifier of the PLP in which a resource is transmitted.

source_IP_address: A source IP address of an IP packet in which aresource is transmitted.

destination_IP_address: A destination IP address of an IP packet inwhich a resource is transmitted.

destination_Port: A destination port number of an IP packet in which aresource is transmitted.

session_id: A session ID of a transmission session protocol in which aresource is transmitted, for example, may be a Transport SessionIdentifier value in the case of the LCT session.

broadcast_stream_id: An identifier of a broadcast stream in which aresource is transmitted.

(2) In the case that a resource location type is 0x02, a resourcelocation may be signaled by the following information.

PLP_ID: An identifier of the PLP in which a resource is transmitted.

destination_IP_address: A destination IP address of an IP packet inwhich a resource is transmitted.

destination_Port: A destination port number of an IP packet in which aresource is transmitted.

broadcast_stream_id: An identifier of a broadcast stream in which aresource is transmitted.

(3) In the case that a resource location type is 0x03, a resourcelocation may be signaled by the following information.

resource_download_url_str_length: A length of URL in which a resourcedownload is available.

resource_download_url_str: URL in which a resource download isavailable.

(4) In the case that a resource location type is 0x04, a resourcelocation may be signaled by the following information.

resource_data_length: A length of an embedded resource.

resource_data_bytes( ): Embedded Resource Data

Accordingly, in the embodiment of FIG. 25, the present invention mayprovide an additional EA related content, and in such a case, thepresent invention may provide a method for transmitting the additionalEA related content and a signaling method for supporting it.

FIG. 26 illustrates EA information according to another embodiment ofthe present invention.

The embodiment of FIG. 26 proposes a structure of the EA information (EAtable) including one or more EAs. The embodiment of the EA table or thedescription syntax including one or more EAs is as shown in FIG. 26. Thestructure of binary syntax proposed in the present invention may beconstructed with XML format. The description of the fields included inthe EA table (EA message) syntax of FIG. 26 is as below.

In FIG. 26, the EA information includes the signaling information withrespect to at least one EA contents. The transmission type of the EAcontent may be a type embedded in the EA information, a type transmittedin a broadcast network or a type transmitted in broadband. The format ofthe EA content may be distinguished by EA format information ea_format.The format of the EA content may correspond to a CAP format, a binarysyntax format or an XML format.

table_id: A unique ID of a table given to EAT table

EAT_protocol_version: A protocol version of EAT

section_length: A length of a table

EAT_version_number: A version number of table data

current_section_number: A number of the current table

last_section_number: The number of total tables transmitted

ea_id: A unique identifier given per an emergency alert issued a day

ea_transfer_type: A value representing a path through which the EA istransmitted. In the case that it is 0x01, this means that the EA istransmitted with being embedded in a table. In the case that it is 0x02,this means the case that the EA is transmitted in a broadcast network.In the case that it is 0x03, this means the case that the EA istransmitted in broadband.

ea_format: This field means a format of the emergency informationtransmitted through the EAT. In the case that it is 0x01, the CAP istransmitted, and in the case that it is 0x02, this means a predefinedmessage format of a binary syntax form. In the case that it is 0x03,this means a predefined message format of an XML form. In the othercase, it is defined as a reserved field for the Future Extensibility.

encoding_type: This field an encoding type of the CAP in the case thatit is transmitted with a CAP message. This field means 0x00 (nocompression) or 0x01 (DEFLATE).

CAP_data_length: This field represents a length of the CAP in the casethat the emergency alert is transmitted through the CAP.

CAP_data_bytes( ): Actual CAP bytes transmitted with being embedded in atable

Emergency_Alert( ): An alert message of a Predefined Emergency AlertType defined in section 7

broadcast_stream_id: A stream identifier of a broadcast, in the casethat it is transmitted with different IP packet, not embedded in atable. In the case that it is defined as 0x00, this means that it istransmitted with the same broadcast_stream_id as the corresponding EAT.

PLP_ID: An identifier of PLP which is transmitted, in the case that itis transmitted with different PLP, not embedded in a table.

sourceIPaddress: A source IP address of a UDP/IP session, in the casethat it is transmitted with different UDP/IP session, not embedded in atable.

destinationIPaddress: A destination IP address of a UDP/IP session, inthe case that it is transmitted with different UDP/IP session, notembedded in a table.

destinationPort: A destination port number of a UDP/IP session, in thecase that it is transmitted with different UDP/IP session, not embeddedin a table.

tsi: A transport session identifier of an LCT session which istransmitted, in the case that it is transmitted with different LCTsession, not embedded in a table.

ea_url_length: In the case that an Emergency Alert is transmitted inbroadband, this field represents a length of URL which is transmitted.

ea_url: A path URL through which an Emergency Alert is transmitted inbroadband

FIG. 27 illustrates an embodiment of signaling an embedded EA in an EAmessage.

It is identified that the ea_transfer_type field value is 0x01 and theEA is embedded in the EA table. In addition, in the case that theea_format value is 0x01, this may represent that the embedded EA is theCAP data, and in the case that the ea_format value is 0x02, this mayrepresent that the embedded EA is the predefined EA format. Furthermore,two EA messages TOR_ALERT_001 and HUR_ALERT_001 may be transmitted withbeing included in the EAT. The first EA message TOR_ALERT_001 may betransmitted with the CAP, and the second EA message HUR_ALERT_001 may betransmitted with the predefined EA format.

FIG. 28 illustrates an embodiment of signaling an EA with a separatesession in an EA message.

The ea_transfer_type field value is 0x02, which may represent that analert message is transmitted with a separate session. In addition, inthe case that the ea_format value is 0x01, this may represent that thetransmitted message is the CAP data, and in the case that the ea_formatvalue is 0x02, this may represent that the transmitted message is thepredefined EA format.

Hereinafter, the present invention proposes a method for transmittingrich media contents in relation to the EA and the EAT syntax therefor.As an embodiment, the EA related rich media may be transmitted throughthe EAS NRT service signaling.

FIG. 29 illustrates syntax of the EA information according to anotherembodiment of the present invention.

FIG. 29 shows the EA information defined to transmit the rich media inrelation to the EA. The fields in the table of FIG. 29 as the same asFIG. 26 will not described repeatedly.

The EA table of FIG. 29 includes EAS_NRT_Service_id information. Therich media associated with an EA may be transmitted through the EAS NRTservice signaling. The present invention proposes a method of providingan EAS NRT service ID associated with a single EA of the EAT, andsignaling the rich media contents associated with the EA throughsignaling of the corresponding service. The EAS_NRT_Service_idinformation represents a service identifier for providing the rich mediaassociated with the EA.

In FIG. 29, a type for the rich media content being transmitted may beCAP, broadcast or broadband, and the EA information provides theresource location information for each type. In the case that atransmission type of the rich media is broadcast, the EA information mayprovide at least one field of a broadcast stream ID, a PLP ID, a sourceIP address, a destination IP address, a destination port number and aTSI. In the case that the rich media content is transmitted in an LCTsession, the TSI represents a transport session identifier (TSI) of thecorresponding LCT session. That is, the TSI may represent the LCTchannel information in which the rich media content is transmitted. Inthe case that a transmission type of the rich media content isbroadband, the EA information includes the URL information fordownloading the rich media content.

FIG. 30 illustrates an ENRT-IT (EA related NRT information table) forrich media contents signaling according to an embodiment of the presentinvention.

The description for the fields included in FIG. 30 is as follows.

table_id: A unique ID of the table given to the ENRT-IT table

ENRT_IT_protocol_version: A protocol version of the ENRT-IT

section_length: A length of the table

ENRT-IT_version_number: A version number of the table data

current_section_number: A section number of the current table

last_section_number: The number of total tables that are transmitted

service_id: An identifier of the EAS NRT service specified with theservice associated with the EA in the EAT

num_rich_media_contents: The number of rich media contents transmittedthrough the EAS NRT service

content_linkage: This field specifies a value mapped to Content linkagespecified in FDT (File Delivery Table). A receiver may obtain theinformation of each file defined in the FDT using the value. This fieldmay also represent a URL matched to the content-location attribute ofthe corresponding file element in the FDT of the LCT channel thatdelivers a file.

expiration: An expiration date of the corresponding content

size: A size of the corresponding content

time_slot_info: time_slot information of the corresponding content

content_description_length: A length of description string thatrepresents brief information of the corresponding content

content_description: A string that represents brief information of thecorresponding content

name_length: A length of the name of the corresponding content

name: A name of the corresponding content

availableOnInet: A flag representing whether an acquisition of thecorresponding content is available through broadband

content_url_length: A length of broadband URL of the correspondingcontent

content_url: A broadband URL of the corresponding content

FIG. 31 illustrates a signaling structure of rich media contentsaccording to an embodiment of the present invention.

As described above, the EA related rich media contents may betransmitted through broadcast or broadband. FIG. 31 shows a signalingstructure for the case that the rich media contents are streamingthrough broadcast. That is, in the embodiment of FIG. 31, the rich mediacontents are provided as an EA service.

As described above, the EA information may include an ID of the servicein which the EA related rich media contents are transmitted. In theembodiment of FIG. 31, the EAS NRT service ID is 0x0911.

Accordingly, a broadcast receiver may identify the ID of the service inwhich the EA related rich media contents are transmitted, and may checkthe SLS information for the corresponding ID from the SLT information.That is, the broadcast receiver may identify the service in which the EArelated rich media contents are transmitted from the SLT information,and may obtain the resource information (IP information, portinformation, TSI-SLS information, etc.) for the SLS that signals theinformation for the service. The broadcast receiver may obtain the SLSinformation for the service that delivers the EA related rich mediacontents, and may receive the service data, that is, the rich mediacontents by using the SLS information.

For this, the service category information of the SLT may include an EASservice category. That is, the service category informationservice_category of FIG. 14 may further include an EAS service inaddition to a linear A/V service, a linear audio only service, and anApp-based service, as a service category.

An EA message may wake up or not a receiver based on a priority of amessage. For this, a wake-up indicator may be signaled. Otherwise, basedon the priority, the receiver may wake up only in the case that an EAmessage of higher priority than a specific value is received. Thewake-up operation may occur in the case that a TV or a broadcastreceiver is turned off or in a standby mode.

In the case that a user experiences wake-up of a broadcast receiverbased on a wake-up signal and turns off the broadcast receiver, thebroadcast receiver should not wake up for an identical EA message.Accordingly, in order for the receiver to know whether a wake-up signalis an identical wake-up signal or a new/updated wake-up signal, awake-up indicator and/or a wake-up version may be signaled. In the casethat multiple alert messages are received simultaneously, the message ofthe highest priority should wake up the broadcast receiver. In such acase, the broadcast receiver may display all EA messages according tothe priority.

FIG. 32 is a diagram illustrating a method for waking up a broadcastreceiver or processing an EA message according to an embodiment of thepresent invention.

FIG. 32(a) shows the case of using a version of a wake-up signal itself,and FIG. 32(b) shows the case of using a version of an EA message.

In FIG. 32, a broadcast receiver may decode a bootstrap signal of aphysical layer signal frame. The bootstrap signal of the signal frameperforms the role of an entry point with respect to a transmittedsignal, and has a fixed configuration public to all receivers. Thebootstrap information may include wake-up information eas_wake_up. Thebroadcast signal receiver may wake up from a standby mode to an activemode based on a value of the wake-up information.

In FIG. 32(a), the broadcast receiver that enters the active mode maydecode L1 signaling information, and may check the wake-up versioninformation included in the L1 signaling information. In addition, thebroadcast receiver may obtain EA information (EAT) in the case that thewake-up version is new.

In FIG. 32(b), the broadcast receiver that enters the active mode mayobtain the EA information, and may check the version information of theEA information included in the EA information. In addition, thebroadcast receiver may process the EA information in the case that thewake-up version is new.

As described in FIG. 32, the wake-up information may include wake-upindication information that indicates wake-up of the receiver or versioninformation that determines whether to obtain or process the EAinformation. The version information may represent a version of thewake-up information or a version of the EA information. However, in thecase of representing a version of the wake-up information, the receiveris not even required to obtain and process the EA information, andaccordingly, the receiver may further decrease unnecessary processing.Such wake-up indication information and the version information may bereferred to as wake-up information.

FIG. 33 illustrates an operation of a broadcast receiver according towake-up information.

In FIG. 33, a signal frame of a physical layer may include PhysicalLayer Signaling (PLS) information, and the PLS information may provideL1 signaling information. The L1 signaling information may includeversion information, and the version information may provide a wake-upindicator and a wake-up version. As an embodiment, a broadcast receivermay refer to a version (EAT, message_version) of an EA message.

On timing t1, the receiver may detect wake-up information, and mayprocess or provide an EA message by waking up accordingly. The EAmessage may include the content that Hurricane is coming.

On timing t2, the receiver detects the wake-up information. The wake-upinformation detected by the receiver includes a wake-up indication.However, the version information of the detected wake-up information isthe same as the version information of the wake-up information receivedon timing t1. Accordingly, the receiver does not process or provide theEA message. The receiver may not wake up.

On timing t3, the receiver detects the wake-up information. The wake-upinformation detected by the receiver includes a wake-up indication.However, the version information of the detected wake-up information hashigher version than the version information of the wake-up informationreceived on timing t1. Accordingly, the receiver may process or providethe EA message. The EA message may include the content that tornado iscoming.

FIG. 34 illustrates a method for transmitting a broadcast signalaccording to an embodiment of the present invention.

A broadcast transmitter may encode a broadcast service data based on adelivery protocol (step, S34010). The broadcast service data is a datathat supports a function provided by a broadcast service, and mayinclude at least one of audio, video and text data. The broadcastservice data may also be referred to as a service data component or aservice component.

The broadcast transmitter generates Service Layer Signaling (SLS)information and SLT information for discovering and obtaining thebroadcast service data (step, S34020). The SLS information provides adiscovery and an acquisition of the broadcast service data, and the SLTinformation provides a discovery of the SLS information and a basicservice list building. However, the SLT information may be generatedafter encoding based on generation and delivery protocol of the SLSinformation. In such an embodiment, the broadcast transmitter may encodethe SLS information based on the generation and delivery protocol, andgenerate the SLT information, and then, perform the UDP/IP encapsulationof each service data, the SLS information and the SLT information. Asanother embodiment, the broadcast transmitter may generate the SLSinformation for the broadcast service data, and encode the broadcastservice data and the SLS information based on the delivery protocol, andthen generate the SLT information. That is, the order and theconstruction of performing steps S34010 to S34030 may be changedaccording to an embodiment.

The broadcast transmitter may encode the SLS information based on thedelivery protocol (step, S34030). The deliver protocol in which thebroadcast service data and the SLS information are encoded may includeat least one of Real-Time Object Delivery over Unidirectional Transport(ROUTE) protocol or MPEG Media Transport (MMT) protocol. However, thesame delivery protocol may be applied to the broadcast service data andthe SLS information. That is, in the case that the broadcast servicedata is encoded by MMT protocol, the SLS information for the broadcastservice data may be encoded by the MMT protocol. In addition, in thecase that the broadcast service data is encoded by ROUTE protocol, theSLS information for the broadcast service may be encoded by ROUTEprotocol.

The broadcast trasmitter may respectively UDP (User DatagramProtocol)/IP (Internet Protocol) encapsulate the broadcast service data,the SLS information and the LLS information including the SLTinformation (step, S34040). The broadcast service data, the SLSinformation and the LLS information which is performed through UDP/IPencapsulation is an IP packet, and may be distinguished by an IP addressand a port number. Accordingly, the data transmitted by the broadcastreceiver according to the present invention may operate/be distinguishedbased on IP.

The broadcast transmitter may generate a signal frame by performingphysical layer processing of the broadcast service data, the SLSinformation and the LLS information (step, S34050). The signal frame mayinclude physical layer signaling information (L1 signaling information).

In the UDP/IP encapsulation, the LLS information may be encapsulatedwith an IP packet that has a predetermined address and port number. Thatis, the LLS information may be carried as a payload of an IP packet thathas a well-known address and port number. In addition, the LLSinformation may further include the Emergency Alert (EA) relatedsignaling information.

A broadcaster may be needed to broadcast an alert for an emergencysituation when the emergency situation occurs. The signaling informationfor providing such EA (emergency alert) may also be referred to as EArelated signaling information. Furthermore, the EA related signalinginformation may correspond to a Common Alerting Protocol (CAP) message.The CAP represents a simple but general format that mayexchange/communicate all EAs over all types of networks.

The rich media content may be provided as the EA. For this, the EArelated signaling information may include the signaling information fortransmitting the EA related rich media content. In the case that therich media content is delivered through broadband, the EA relatedsignaling information may indicate the Uniform Resource Locator (URL)information that may receive the rich media content. In the case thatthe rich media content is delivered through broadcast, the EA relatedsignaling information may indicate the LCT channel information in whichthe rich media content is delivered.

As described above, the SLT information includes service categoryinformation. The service category information may include a linear A/Vservice, a linear audio only service, an application-based service andan EA service, and may further include an EA service. In addition, therich media content may be delivered through the EA service. In thiscase, the EA related signaling information includes the service IDinformation that delivers the rich media content.

In the case that a signal frame includes the EA related signalinginformation, the physical layer signaling information of the signalframe may include a wake-up signal (wake-up information) indicating awake-up from a standby mode of a receiver and a version of the wake-up.

In the present invention, the LLS information is not encoded based onthe delivery protocol. Accordingly, the receiver may obtain the SLTinformation or the EA related signaling information included in the LLSinformation with less decoding operation. Particularly, since the LLSinformation is distinguished by a well-known IP address/port number, thereceiver may start providing a broadcast service quickly by receivingthe LLS information with the start of a broadcast signal reception.

Since the EA related signaling information is included in the LLSinformation, the receiver may also provide the EA relatedmessage/content quickly by receiving/decoding to a user. Particularly,the EA related signaling information is used as a CAP message, and thus,the compatibility may be increased. The EA related rich media contentmay be transmitted separately from the EA related signaling information,and may be transmitted through broadcast or broadband. For each of thecases, the EA related signaling information provides the resourceinformation (URL information and/or LCT channel information) requiredfor the receiver to receive the rich media content throughbroadcast/broadband. Accordingly, even in the case that the receiver isunable to receive the rich media content in a path, the receiver mayreceive the rich media content in other path, and accordingly, thesafety of EA content delivery for a disaster situation may be increased.

The rich media service for the EA may be delivered through broadcastservice. Accordingly, the service category information should identifythe EA service therefor. The service category information maydistinguish a linear A/V service, a linear audio only service, anapplication-based service and an EA service. In addition, in this case,the EA related signaling information may include service ID informationof the EA service. Since the receiver may receive the EA content as oneof the broadcast service, in this case, the receiver may deliver the EAcontent while minimizing an operation change of the broadcast system.

FIG. 35 illustrates a broadcast signal transmitter and a broadcastsignal receiver according to an embodiment of the present invention.

A broadcast signal transmitter 35100 may include a signaling generator35110, a delivery layer encoder 35120, a UDP/IP encapsulator 35130 and aphysical layer processor 35140.

The signaling generator 35110 may generate the Service Layer Signaling(SLS) information that provides a discovery and acquisition of thebroadcast service data and the Service List Table (SLT) information thatprovides a basic service list building and an acquisition of the SLSinformation. The delivery layer encoder 35120 may encode the broadcastservice data and the SLS information based on at least one deliveryprotocol of Real-Time Object Delivery over Unidirectional Transport(ROUTE) protocol or MPEG Media Transport (MMT) protocol. The UDP/IPencapsulator 35130 may respectively UDP (User Datagram Protocol)/IP(Internet Protocol) encapsulate the service data, the SLS informationand the Low level Signaling (LLS) information including the SLTinformation. The physical layer processor 35140 may generate a signalframe by performing physical layer processing of the broadcast servicedata, the SLS information and the SLT information.

The broadcast signal transmitter 35100 of FIG. 35 performs the methodfor transmitting a broadcast signal described above, and the samedescription is not repeated.

The broadcast signal receiver 35200 may include a signaling parser35210, a delivery layer decoder 35220, a UDP/IP packet parser 35230 anda physical layer parser 35240. The broadcast signal receiver 35200 mayperform an inverse operation of the broadcast signal transmitter.

The physical layer parser 35240 may perform physical layer processing ofa received signal frame and output a UDP/IP packet stream. The UDP/IPpacket parser 35230 may decapsulate the received IP packet stream andoutput a service component data. The delivery layer decoder 35220 maydecode the service component data according to the delivery protocol.The signaling parser 35210 may obtain and parse signaling informationand control an operation of the broadcast signal receiver. For example,the broadcast signal receiver may obtain the SLT, and may obtain an IPaddress and a port number of a required SLS by parsing the SLT. Inaddition, the broadcast signal receiver may obtain a transmission pathof a required service data by parsing the SLS. Furthermore, thebroadcast signal receiver may perform physical layer parsing, UDP/IPdecapsulating and delivery layer decoding of a required broadcast datathroughout overall paths, and may provide the corresponding broadcastdata to a user.

In FIG. 35, sub-units of the broadcast signal transmitter and thebroadcast signal receiver are distinguished according to the operations.That is, a single sub-unit is not necessary to be implemented as asingle physical processor, but a single sub-unit may be implemented as aplurality of physical processors or a plurality of sub-units may beimplemented as a single physical processor.

The steps described in the aforementioned embodiments can be performedby hardware/processors. Modules/blocks/units described in the aboveembodiments can operate as hardware/processors. In addition, the methodsproposed by the present invention can be executed as a code. Such codecan be written on a processor-readable storage medium and thus can beread by a processor provided by an apparatus.

While the embodiments have been described with reference to respectivedrawings for convenience, the embodiments may be combined to implement anew embodiment. The apparatus and method according to the presentinvention are not limited to the configurations and methods of theabove-described embodiments and the whole or some of the embodiments maybe selectively combined to obtain various modifications.

Meanwhile, the method proposed in the present invention may beimplemented as processor-readable code stored in a processor-readablerecording medium included in a network device. The processor-readablerecording medium includes all kinds of recording media storing datareadable by a processor. Examples of the processor-readable recordingmedium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk,an optical data storage device and the like, and an implementation ascarrier waves such as transmission over the Internet. In addition, theprocessor-readable recording medium may be distributed to computersystems connected through a network, stored and executed as codereadable in a distributed manner.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims. Such modifications should notbe individually understood from the technical spirit or prospect of thepresent invention.

Those skilled in the art will appreciate that the present invention maybe changed and modified in various ways without departing from thespirit and essential characteristics of the present invention.Therefore, the present invention is intended to include change andmodification of the present invention provided in the accompanyingclaims and the equivalency range.

In the specification, both the apparatus invention and the methodinvention are mentioned, and description of both the apparatus inventionand the method invention can be applied complementarily.

MODE FOR INVENTION

Various embodiments have been described in the Best Mode for theInvention.

INDUSTRIAL APPLICABILITY

The present invention is used in a series of broadcast signaltransmission/reception fields.

Those skilled in the art will appreciate that the present invention maybe changed and modified in various ways without departing from thespirit and essential characteristics of the present invention.Therefore, the present invention is intended to include change andmodification of the present invention provided in the accompanyingclaims and the equivalency range.

1. A method for transmitting a broadcast signal, comprising: generatingSLS information and SLT information with respect to broadcast servicedata, wherein the SLS information provides a discovery and anacquisition of the broadcast service data, and wherein the SLTinformation provides a discovery of the SLS information and building ofa basic service list; processing the broadcast service data and the SLSinformation based on the delivery protocol; UDP (User DatagramProtocol)/IP (Internet Protocol) encapsulating broadcast service data,the SLS information and Low level Signaling (LLS) information includingthe the SLT information; and generating a signal frame by physical layerprocessing of the broadcast service data, the SLS information and theLLS information, wherein the delivery protocol includes at least one ofReal-Time Object Delivery over Unidirectional Transport (ROUTE) protocolor MPEG Media Transport (MMT) protocol.
 2. The method for transmitting abroadcast signal of claim 1, wherein the LLS information is carried as apayload of an IP packet that has a predetermined address and portnumber.
 3. The method for transmitting a broadcast signal of claim 2,wherein the LLS information includes Emergency Alert (EA) relatedsignaling information.
 4. The method for transmitting a broadcast signalof claim 3, wherein the EA related signaling information corresponds toa Common Alerting Protocol (CAP) message.
 5. The method for transmittinga broadcast signal of claim 4, wherein the EA related signalinginformation includes signaling information for media contenttransmission, when a rich media content is delivered through broadband,wherein the EA related signaling information indicates Uniform ResourceLocator (URL) information for receiving the rich media content, and whenthe rich media content is delivered through broadcast, wherein the EArelated signaling information indicates LCT channel related informationin which the rich media content is delivered.
 6. The method fortransmitting a broadcast signal of claim 4, wherein the SLT informationincludes service category information, wherein a service categoryindicated by the service category information includes a linear A/Vservice, a linear audio only service, an application-based service andan EA service.
 7. The method for transmitting a broadcast signal ofclaim 3, when the signal frame includes the EA related signalinginformation, wherein physical layer signaling information of the signalframe indicates wake-up from a standby mode of a receiver, and includeswake-up signal indicating a wake-up version.
 8. A broadcast signaltransmitter, comprising: a signaling generator configured to generateService Layer Signaling (SLS) information providing a discovery and anacquisition of a broadcast service data and and Service List Table (SLT)information providing building of a basic service list and anacquisition of the SLS information; a delivery layer processorconfigured to process the broadcast service data and the SLS informationbased on at least one delivery protocol of Real-Time Object Deliveryover Unidirectional Transport (ROUTE) protocol or MPEG Media Transport(MMT) protocol; a UDP/IP encapsulator configured to respectively UDP(User Datagram Protocol)/IP (Internet Protocol) encapsulate thebroadcast service data, the SLS information and Low level Signaling(LLS) information including the SLT information; and a physical layerprocessor configured to generate a signal frame by performing physicallayer processing of the broadcast service data, the SLS information andthe LLS information.
 9. The broadcast signal transmitter of claim 8,wherein the LLS information is carried as a payload of an IP packet thathas a predetermined address and port number.
 10. The broadcast signaltransmitter of claim 9, wherein the LLS information includes EmergencyAlert (EA) related signaling information.
 11. The broadcast signaltransmitter of claim 10, wherein the EA related signaling informationcorresponds to a Common Alerting Protocol (CAP) message.
 12. Thebroadcast signal transmitter of claim 11, wherein the EA relatedsignaling information includes signaling information for media contenttransmission, when a rich media content is delivered through broadband,wherein the EA related signaling information indicates Uniform ResourceLocator (URL) information for receiving the rich media content, and whenthe rich media content is delivered through broadcast, wherein the EArelated signaling information indicates LCT channel related informationin which the rich media content is delivered.
 13. The broadcast signaltransmitter of claim 11, wherein the SLT information includes servicecategory information, wherein a service category indicated by theservice category information includes a linear A/V service, a linearaudio only service, an application-based service and an EA service. 14.The method for transmitting a broadcast signal of claim 10, when thesignal frame includes the EA related signaling information, whereinphysical layer signaling information of the signal frame includeswake-up signal indicating wake-up from a standby mode of a receiver andindicating a wake-up version.